AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON DECEMBER 5, 2001.

                                            REGISTRATION STATEMENT NO. 333-
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                         ------------------------------
                                    FORM S-3
            REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933
                         ------------------------------
                        AFFILIATED MANAGERS GROUP, INC.
             (Exact Name of Registrant as specified in its charter)


                       
        DELAWARE                       04-3218510
(State of Incorporation)  (I.R.S. Employer Identification No.)


                         ------------------------------

                      TWO INTERNATIONAL PLACE, 23RD FLOOR
                          BOSTON, MASSACHUSETTS 02110
                                 (617) 747-3300
              (Address, including zip code, and telephone number,
       including area code, of Registrant's principal executive offices)
                         ------------------------------

                                WILLIAM J. NUTT
               CHIEF EXECUTIVE OFFICER AND CHAIRMAN OF THE BOARD
                        Affiliated Managers Group, Inc.
                      Two International Place, 23rd Floor
                          Boston, Massachusetts 02110
                                 (617) 747-3300
           (Name, address, including zip code, and telephone number,
                   including area code, of agent for service)
                         ------------------------------

                                WITH COPIES TO:
                          Martin Carmichael III, P.C.
                              Goodwin Procter LLP
                                 Exchange Place
                          Boston, Massachusetts 02109
                                 (617) 570-1000

    APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO THE PUBLIC: From time
to time after this Registration Statement becomes effective.

    If the only securities being registered on this form are being offered
pursuant to dividend or interest reinvestment plans, please check the following
box. / /

    If any of the securities being registered on this form are to be offered on
a delayed or continuous basis pursuant to Rule 415 under the Securities Act of
1933, other than securities offered only in connection with dividend or interest
reinvestment plans, check the following box. /X/

    If this form is used to register additional securities for an offering
pursuant to Rule 462(b) under the Securities Act, please check the following box
and list the Securities Act Registration Statement number of the earlier
effective registration statement for the same offering. / /

    If this form is a post-effective amendment filed pursuant to Rule 462(c)
under the Securities Act, check the following box and list the Securities Act
Registration Statement number of the earlier effective registration statement
for the same offering. / /

    If delivery of the Prospectus is expected to be made pursuant to Rule 434,
please check the following box. / /
                         ------------------------------

                        CALCULATION OF REGISTRATION FEE



                                                           PROPOSED MAXIMUM        PROPOSED MAXIMUM
  TITLE OF SECURITIES BEING          AMOUNT TO BE              OFFERING               AGGREGATE               AMOUNT OF
          REGISTERED                REGISTERED(1)         PRICE PER UNIT(2)       OFFERING PRICE(3)      REGISTRATION FEE(4)
                                                                                            
Debt Securities...............
Preferred Stock...............
Common Stock..................
Stock Purchase Contracts......
Stock Purchase Units..........
Total.........................       $750,000,000                N.A.                $750,000,000              $179,250


(1) The amount to be registered consists of up to $750,000,000 of an
    indeterminate number of Debt Securities, Preferred Stock, Common Stock,
    Stock Purchase Contracts and/or Stock Purchase Units. Pursuant to Rule 429
    under the Securities Act of 1933, as amended (the "Securities Act"), there
    is also being registered hereunder such currently indeterminate number of
    (a) shares of Common Stock as may be issued upon (i) conversion of the Debt
    Securities or the Preferred Stock, or (ii) the sale of Common Stock pursuant
    to the Stock Purchase Contracts registered hereby and (b) shares of
    Preferred Stock as may be issued upon conversion of the Debt Securities
    registered hereby.

(2) The proposed maximum offering price per unit has been omitted pursuant to
    Securities Act Release No. 6964.

(3) Estimated solely for purposes of computing the registration fee. No separate
    consideration will be received for securities issued upon conversion of Debt
    Securities or Preferred Stock.

(4) The registration fee has been calculated in accordance with Rule 457(o)
    under the Securities Act.

    THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR
DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL
FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION
STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(A) OF
THE SECURITIES ACT OF 1933 OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME
EFFECTIVE ON SUCH DATE AS THE COMMISSION, ACTING PURSUANT TO SAID SECTION 8(A),
MAY DETERMINE.

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

                 SUBJECT TO COMPLETION, DATED DECEMBER 5, 2001
THE INFORMATION IN THIS PROSPECTUS IS NOT COMPLETE AND MAY BE CHANGED. WE MAY
NOT SELL THESE SECURITIES UNTIL THE REGISTRATION STATEMENT FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION IS EFFECTIVE. THIS PROSPECTUS IS NOT AN OFFER
TO SELL THESE SECURITIES AND IT IS NOT SOLICITING AN OFFER TO BUY THESE
SECURITIES IN ANY STATE WHERE THE OFFER OR SALE IS NOT PERMITTED.

                                   PROSPECTUS

[LOGO]

                        AFFILIATED MANAGERS GROUP, INC.

                                  $750,000,000
                                DEBT SECURITIES
                                PREFERRED STOCK
                                  COMMON STOCK
               STOCK PURCHASE CONTRACTS AND STOCK PURCHASE UNITS

                               ------------------

    This prospectus provides you with a general description of debt and equity
securities that Affiliated Managers Group, Inc. may offer and sell from time to
time. Each time we sell securities we will provide a prospectus supplement that
will contain specific information about the terms of that sale and may add to or
update the information in this prospectus. You should read this prospectus and
any prospectus supplement carefully before you invest in our securities.

    Our common stock is traded on the New York Stock Exchange under the symbol
"AMG."

                            ------------------------

                                December 5, 2001

                            ------------------------

    Neither the Securities and Exchange Commission nor any state securities
commission has approved or disapproved of these securities or determined if this
prospectus is truthful or complete. Any representation to the contrary is a
criminal offense.

                               TABLE OF CONTENTS



                                                                PAGE
                                                              --------
                                                           
About this Prospectus.......................................      1

Where You Can Find More Information.........................      1

Forward-looking Statements..................................      2

About Affiliated Managers Group, Inc........................      3

Ratios of Earnings to Fixed Charges.........................      3

How We Intend to Use the Proceeds...........................      3

Description of the Debt Securities..........................      4

Description of Preferred Stock..............................     19

Description of Common Stock.................................     25

Description of the Stock Purchase Contracts and the Stock
  Purchase Units............................................     26

How We Plan to Offer and Sell the Securities................     27

Experts.....................................................     29

Legal Opinions..............................................     29


                                      (i)

                             ABOUT THIS PROSPECTUS

    This prospectus is part of a registration statement that we filed with the
SEC utilizing a shelf registration process. Under this shelf registration
process, we may sell any combination of the securities described in this
prospectus in one or more offerings up to a total dollar amount of $750,000,000.
This prospectus provides you with a general description of the securities we may
offer. Each time we sell securities, we will provide a prospectus supplement
that will contain specific information about the terms of that specific
offering. The prospectus supplement may also add, update or change information
contained in this prospectus. You should read both this prospectus and any
prospectus supplement together with the additional information described under
the heading "Where You Can Find More Information."

    You should read this entire prospectus, including the information
incorporated by reference, before making an investment decision. Unless the
context otherwise requires, all references to "we," "us," "our," "our company,"
"Affiliated Managers Group," or similar expressions in this prospectus refer to
Affiliated Managers Group, Inc., a Delaware corporation, and not its affiliates
or other subsidiaries.

                      WHERE YOU CAN FIND MORE INFORMATION

    We file annual, quarterly and special reports, proxy statements and other
information with the SEC. You may read and copy any document we file at the
SEC's Public Reference Room at 450 Fifth Street, N.W., Washington, D.C. 20549.
You may call the SEC at 1-800-SEC-0330 for further information on the operation
of the Public Reference Room. Our SEC filings are also available to the public
from the SEC's Web site at http://www.sec.gov. In addition, you may read our SEC
filings at the offices of the New York Stock Exchange (NYSE), which is located
at 20 Broad Street, New York, New York 10005. Our SEC filings are available at
the NYSE because our common stock is listed on the NYSE.

    We have the authority to designate and issue more than one class or series
of stock having various preferences, conversion and other rights, voting powers,
restrictions, limitations as to dividends, qualifications, and terms and
conditions of redemption. See "Description of Preferred Stock" and "Description
of Common Stock." We will furnish a full statement of the relative rights and
preferences of each class or series of our stock which has been so designated
and any restrictions on the ownership or transfer of our stock to any
stockholder upon request and without charge. Written requests for such copies
should be directed to: Affiliated Managers Group, Inc., Two International Place,
23rd Floor, Boston, Massachusetts 02110, Attention: Darrell W. Crate--Executive
Vice President, Chief Financial Officer and Treasurer.

    The SEC allows us to incorporate by reference the information and reports we
file with it, which means that we can disclose important information to you by
referring you to these documents. The information incorporated by reference is
an important part of this prospectus, and information that we file later with
the SEC will automatically update and supersede the information already
incorporated by reference. We are incorporating by reference the documents
listed below, which we have already filed with the SEC, and any future filings
we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities
Exchange Act of 1934 until we sell all of the securities.



SEC FILINGS (FILE NO. 001-13459)                             PERIOD OR DATE FILED
--------------------------------                             --------------------------------
                                                          
Annual Report on Form 10-K.................................  Year ended December 31, 2000
Current Report on Form 8-K.................................  May 4, 2001
Quarterly Report on Form 10-Q..............................  Quarter ended March 31, 2001
Quarterly Report on Form 10-Q..............................  Quarter ended June 30, 2001
Current Report on Form 8-K.................................  August 20, 2001
Current Report on Form 8-K.................................  August 20, 2001
Current Report on Form 8-K.................................  September 20, 2001
Quarterly Report on Form 10-Q..............................  Quarter ended September 30, 2001
Current Report on Form 8-K.................................  November 15, 2001
Current Report on Form 8-K.................................  November 15, 2001



    YOU MAY REQUEST A COPY OF THESE FILINGS, AND ANY EXHIBITS WE HAVE
SPECIFICALLY INCORPORATED BY REFERENCE AS AN EXHIBIT IN THIS PROSPECTUS, AT NO
COST BY WRITING OR TELEPHONING US AT THE FOLLOWING: AFFILIATED MANAGERS
GROUP, INC., TWO INTERNATIONAL PLACE, 23RD FLOOR, BOSTON, MASSACHUSETTS 02110,
ATTENTION: DARRELL W. CRATE--EXECUTIVE VICE PRESIDENT, CHIEF FINANCIAL OFFICER
AND TREASURER. OUR TELEPHONE NUMBER IS (617) 747-3300.

    This prospectus is part of a registration statement we filed with the SEC.
We have incorporated into this registration statement exhibits. You should read
the exhibits carefully for provisions that may be important to you.

    You should rely only on the information incorporated by reference or
provided in this prospectus or any prospectus supplement. We have not authorized
anyone to provide you with different information. We are not making an offer of
these securities in any state where the offer is not permitted. You should not
assume that the information in this prospectus or in the documents incorporated
by reference is accurate as of any date other than the date on the front of this
prospectus or those documents.

                           FORWARD-LOOKING STATEMENTS

    This prospectus, including the information incorporated by reference into
this prospectus, contains statements that are forward-looking statements within
the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the
Securities Exchange Act of 1934. You can identify forward-looking statements by
the use of the words "believe," "expect," "anticipate," "intend," "estimate,"
"assume," "project" and other similar expressions which predict or indicate
future events and trends and which do not relate to historical matters. These
statements include, among other things, statements regarding our intent, belief
or expectations with respect to:

    - potential investment in additional investment management firms;

    - the availability of debt and equity financing to fund investments in
      firms;

    - future borrowing under our credit facility;

    - interest rates and hedging contracts;

    - the impact of new accounting policies;

    - our competition and our Affiliates' competition;

    - changing conditions in the financial and securities markets; and

    - general economic conditions.

    We cannot assure the future results or outcome of the matters described in
any of those statements, which merely reflect our expectations and estimates.
You should not rely on forward-looking statements because they involve known and
unknown risks, uncertainties and other factors, some of which are beyond our
control. These risks, uncertainties and other factors may cause our actual
results, performance or achievements to be materially different from the
anticipated future results, performance or achievements expressed or implied by
the forward-looking statements. Some of the factors that might cause these
differences include, but are not limited to the following:

    - changes in the securities or financial markets or in general economic
      conditions;

    - the availability of equity and debt financing;

    - competition for acquisitions of interests in investment management firms;

    - our ability to complete pending acquisitions; and

                                       2

    - the investment performance of our Affiliates and their ability to
      effectively market their investment strategies.

YOU SHOULD CAREFULLY REVIEW ALL OF THESE FACTORS, AND YOU SHOULD BE AWARE THAT
THERE MAY BE OTHER FACTORS THAT COULD CAUSE SUCH DIFFERENCES.

    We caution you that, while forward-looking statements reflect our estimates
and beliefs, they are not guarantees of future performance. We do not promise to
update any forward-looking statements to reflect changes in underlying
assumptions or factors, new information, future events or other changes.

                     ABOUT AFFILIATED MANAGERS GROUP, INC.

    Affiliated Managers Group is an asset management company that addresses the
succession and transition issues facing the principals of growing mid-sized
investment management firms. Our strategy is to generate growth through the
internal growth of our existing Affiliates, as well as through investments in
new Affiliates. Our transaction structure allows individual members of each
Affiliate's management team to retain significant direct ownership in their firm
while maintaining operating autonomy. In addition, we provide centralized
assistance to our Affiliates in strategic matters, marketing, distribution,
product development and operations. Pro forma for our recent investments in
Friess Associates, LLC and Welch & Forbes, LLC, our affiliated investment
management firms in the aggregate managed over $75 billion in assets at
September 30, 2001. For more information regarding Affiliated Managers Group and
our Affiliates, see "Where You Can Find More Information."

                      RATIOS OF EARNINGS TO FIXED CHARGES

    Our ratio of earnings to fixed charges for each of the periods indicated is
as follows:



                              NINE MONTHS
                                 ENDED        YEAR ENDED     YEAR ENDED     YEAR ENDED     YEAR ENDED     YEAR ENDED
                             SEPTEMBER 30,   DECEMBER 31,   DECEMBER 31,   DECEMBER 31,   DECEMBER 31,   DECEMBER 31,
                                 2001            2000           1999           1998           1997           1996
                             -------------   ------------   ------------   ------------   ------------   ------------
                                                                                       
Ratios.....................        8.8x           9.3x           15.4x          6.1x           2.5x           2.3x


    For the purpose of computing the ratios of earnings to fixed charges,
earnings consist of consolidated income from continuing operations before
provision for income taxes, minority interest and fixed charges, and fixed
charges consist of interest expense, amortization of debt issuance costs and the
portion of rental expense deemed to represent interest.

                       HOW WE INTEND TO USE THE PROCEEDS

    We currently intend to use the net proceeds from the sale of any securities
under this prospectus for general corporate purposes, which may include:

    - the repayment of debt;

    - the possible repurchase of our common stock;

    - the financing of potential investments;

    - working capital; and

    - other purposes as mentioned in any prospectus supplement.

    Pending such use, we may temporarily invest the net proceeds. The precise
amounts and timing of the application of proceeds will depend upon our funding
requirements and the availability of other funds. Except as mentioned in any
prospectus supplement, specific allocations of the proceeds to such purposes
will not have been made at the date of that prospectus supplement.

                                       3

    Based upon our historical and anticipated future growth and our financial
needs, we may engage in additional financings of a character and amount that we
determine as the need arises.

                       DESCRIPTION OF THE DEBT SECURITIES

    This prospectus describes the general terms and provisions of the debt
securities. When we offer to sell a particular series of debt securities, we
will describe the specific terms of the securities in a supplement to this
prospectus. The prospectus supplement will also indicate whether the general
terms and provisions described in this prospectus apply to a particular series
of debt securities. You should read the actual indenture if you do not fully
understand a term or the way we use it in this prospectus.

    We may offer senior debt securities or subordinated debt securities. The
senior debt securities will be issued under an indenture, dated as of a date
prior to such issuance, between us and a trustee, as amended or supplemented
from time to time. We will refer to any such indenture throughout this
prospectus as the "senior indenture." Any subordinated debt securities will be
issued under a separate indenture, dated as of a date prior to such issuance,
between us and the trustee. We will refer to any such indenture throughout this
prospectus as the "subordinated indenture" and to a trustee under any senior or
subordinated indenture as the "trustee." The senior indenture and the
subordinated indenture are sometimes collectively referred to in this prospectus
as the "indentures." The indentures will be subject to and governed by the Trust
Indenture Act of 1939. We included copies of the indentures as exhibits to our
registration statement and they are incorporated into this prospectus by
reference. The following summarizes the material provisions of the indentures,
but may not contain all of the information that is important to you. Except as
otherwise indicated, the terms of the indentures are identical. As used under
this caption, the term "debt securities" includes the debt securities being
offered by this prospectus and all other debt securities issued by us under the
indentures.

GENERAL

    The indentures:

    - do not limit the amount of debt securities that we may issue;

    - allow us to issue debt securities in one or more series;

    - do not require us to issue all of the debt securities of a series at the
      same time;

    - allow us to reopen a series to issue additional debt securities without
      the consent of the debt securityholders of such series; and

    - provide that the debt securities will be unsecured.

    Unless we give you different information in the prospectus supplement, the
senior debt securities will be unsubordinated obligations and will rank equally
with all of our other unsecured and unsubordinated indebtedness. Payments on the
subordinated debt securities will be subordinated to the prior payment in full
of all of our senior indebtedness, as described under "Description of the Debt
Securities--Subordination" and in the applicable prospectus supplement.

    Each indenture provides that we may, but need not, designate more than one
trustee under an indenture. Any trustee under an indenture may resign or be
removed and a successor trustee may be appointed to act with respect to the
series of debt securities administered by the resigning or removed trustee. If
two or more persons are acting as trustee with respect to different series of
debt securities, each trustee shall be a trustee of a trust under the applicable
indenture separate and apart from the trust administered by any other trustee.
Except as otherwise indicated in this prospectus, any action described in this
prospectus to be taken by each trustee may be taken by each trustee with respect
to, and only with respect to, the one or more series of debt securities for
which it is trustee under the applicable indenture.

                                       4

    The prospectus supplement for each offering will provide the following
terms, where applicable:

    - the title of the debt securities and whether they are senior or
      subordinated;

    - the aggregate principal amount of the debt securities being offered, the
      aggregate principal amount of the debt securities outstanding as of the
      most recent practicable date and any limit on their aggregate principal
      amount, including the aggregate principal amount of debt securities
      authorized;

    - the price at which the debt securities will be issued, expressed as a
      percentage of the principal;

    - the portion of the principal payable upon declaration of acceleration of
      the maturity, if other than the principal amount;

    - the date or dates, or the method for determining the date or dates, on
      which the principal of the debt securities will be payable;

    - the fixed or variable interest rate or rates of the debt securities, or
      the method by which the interest rate or rates is determined;

    - the date or dates, or the method for determining the date or dates, from
      which interest will accrue;

    - the dates on which interest will be payable;

    - the record dates for interest payment dates, or the method by which we
      will determine those dates;

    - the persons to whom interest will be payable;

    - the basis upon which interest will be calculated if other than that of a
      360-day year of twelve 30-day months;

    - any make-whole amount, which is the amount in addition to principal and
      interest that is required to be paid to the holder of a debt security as a
      result of any optional redemption or accelerated payment of such debt
      security, or the method for determining the make-whole amount;

    - the place or places where the principal of, and any premium (or make-whole
      amount) and interest on, the debt securities will be payable;

    - where the debt securities may be surrendered for registration of transfer
      or exchange;

    - where notices or demands to or upon us in respect of the debt securities
      and the applicable indenture may be served;

    - the times, prices and other terms and conditions upon which we may redeem
      the debt securities;

    - any obligation we have to redeem, repay or purchase the debt securities
      pursuant to any sinking fund or analogous provision or at the option of
      holders of the debt securities, and the times and prices at which we must
      redeem, repay or purchase the debt securities as a result of such an
      obligation;

    - the currency or currencies in which the debt securities are denominated
      and payable if other than United States dollars, which may be a foreign
      currency or units of two or more foreign currencies or a composite
      currency or currencies and the terms and conditions relating thereto, and
      the manner of determining the equivalent of such foreign currency in
      United States dollars;

    - whether the principal of, and any premium (or make-whole amount) or
      interest on, the debt securities of the series are to be payable, at our
      election or at the election of a holder, in a

                                       5

      currency or currencies other than that in which the debt securities are
      denominated or stated to be payable, and other related terms and
      conditions;

    - whether the amount of payments of principal of, and any premium (or
      make-whole amount) or interest on, the debt securities may be determined
      according to an index, formula or other method and how such amounts will
      be determined;

    - whether the debt securities will be in registered form, bearer form or
      both and (1) if in registered form, the person to whom any interest shall
      be payable, if other than the person in whose name the security is
      registered at the close of business on the regular record date for such
      interest, or (2) if in bearer form, the manner in which, or the person to
      whom, any interest on the security shall be payable if otherwise than upon
      presentation and surrender upon maturity;

    - any restrictions applicable to the offer, sale or delivery of securities
      in bearer form and the terms upon which securities in bearer form of the
      series may be exchanged for securities in registered form of the series
      and vice versa if permitted by applicable laws and regulations;

    - whether any debt securities of the series are to be issuable initially in
      temporary global form and whether any debt securities of the series are to
      be issuable in permanent global form with or without coupons and, if so,
      whether beneficial owners of interests in any such permanent global
      security may or shall be required to exchange their interests for other
      debt securities of the series, and the manner in which interest shall be
      paid;

    - the identity of the depository for securities in registered form, if such
      series are to be issuable as a global security;

    - the date as of which any debt securities in bearer form or in temporary
      global form shall be dated if other than the original issuance date of the
      first security of the series to be issued;

    - the applicability, if any, of the defeasance and covenant defeasance
      provisions described in this prospectus or in the applicable indenture;

    - whether and under what circumstances we will pay any additional amounts on
      the debt securities in respect of any tax, assessment or governmental
      charge and, if so, whether we will have the option to redeem the debt
      securities in lieu of making such a payment;

    - the circumstances, if any, in the applicable prospectus supplement, under
      which beneficial owners of interests in the global security may obtain
      definitive debt securities and the manner in which payments on a permanent
      global debt security will be made if any debt securities are issuable in
      temporary or permanent global form;

    - any provisions granting special rights to holders of securities upon the
      occurrence of such events as specified in the applicable prospectus
      supplement;

    - the name of the applicable trustee and the nature of any material
      relationship with us or any of our Affiliates, and the percentage of debt
      securities of the class necessary to require the trustee to take action;

    - any deletions from, modifications of, or additions to our events of
      default or covenants and any change in the right of any trustee or any of
      the holders to declare the principal amount of any of such debt securities
      due and payable; and

    - any other terms of such debt securities not inconsistent with the
      provisions of the applicable indenture.

    We may issue debt securities at a discount below their principal amount and
provide for less than the entire principal amount thereof to be payable upon
declaration of acceleration of the maturity of

                                       6

the debt securities. We will refer to any such debt securities throughout this
prospectus as "original issue discount securities." The applicable prospectus
supplement will describe the federal income tax consequences and other relevant
considerations applicable to original issue discount securities.

    Except as described under "Description of the Debt Securities--Merger,
consolidation or sale of assets" or as may be set forth in any prospectus
supplement, the debt securities will not contain any provisions that (1) would
limit our ability to incur indebtedness or (2) would afford holders of debt
securities protection in the event of (a) a highly leveraged or similar
transaction involving us or any of our Affiliates or (b) a change of control or
reorganization, restructuring, merger or similar transaction involving us that
may adversely affect the holders of the debt securities. In the future, we may
enter into transactions, such as the sale of all or substantially all of our
assets or a merger or consolidation, that may have an adverse effect on our
ability to service our indebtedness, including the debt securities, by, among
other things, substantially reducing or eliminating our assets.

    Neither the Delaware General Corporation Law nor our governing instruments
define the term "substantially all" as it relates to the sale of assets.
Additionally, Delaware cases interpreting the term "substantially all" rely upon
the facts and circumstances of each particular case. Consequently, to determine
whether a sale of "substantially all" of our assets has occurred, a holder of
debt securities must review the financial and other information that we have
disclosed to the public.

    We will provide you with more information in the applicable prospectus
supplement regarding any deletions, modifications, or additions to the events of
default or covenants that are described below, including any addition of a
covenant or other provision providing event risk or similar protection.

PAYMENT

    Unless we give you different information in the applicable prospectus
supplement, the principal of, and any premium (or make-whole amount) and
interest on, any series of the debt securities will be payable at the corporate
trust office of the trustee. We will provide you with the address of the trustee
in the applicable prospectus supplement. We may also pay interest by mailing a
check to the address of the person entitled to it as it appears in the
applicable register for the debt securities or by wire transfer of funds to that
person at an account maintained within the United States.

    All monies that we pay to a paying agent or a trustee for the payment of the
principal of, and any premium (or make-whole amount) or interest on, any debt
security will be repaid to us if unclaimed at the end of two years after the
obligation underlying payment becomes due and payable. After funds have been
returned to us, the holder of the debt security may look only to us for payment,
without payment of interest for the period which we hold the funds.

DENOMINATION, INTEREST, REGISTRATION AND TRANSFER

    Unless otherwise described in the applicable prospectus supplement, the debt
securities of any series will be issuable in denominations of $1,000 and
integral multiples of $1,000.

                                       7

    Subject to the limitations imposed upon debt securities that are evidenced
by a computerized entry in the records of a depository company rather than by
physical delivery of a note, a holder of debt securities of any series may:

    - exchange them for any authorized denomination of other debt securities of
      the same series and of a like aggregate principal amount and kind upon
      surrender of such debt securities at the corporate trust office of the
      applicable trustee or at the office of any transfer agent that we
      designate for such purpose; and

    - surrender them for registration of transfer or exchange at the corporate
      trust office of the applicable trustee or at the office of any transfer
      agent that we designate for such purpose.

    Every debt security surrendered for registration of transfer or exchange
must be duly endorsed or accompanied by a written instrument of transfer, and
the person requesting such action must provide evidence of title and identity
satisfactory to the applicable trustee or transfer agent. Payment of a service
charge will not be required for any registration of transfer or exchange of any
debt securities, but we or the trustee may require payment of a sum sufficient
to cover any tax or other governmental charge payable in connection therewith.
If in addition to the applicable trustee, the applicable prospectus supplement
refers to any transfer agent initially designated by us for any series of debt
securities, we may at any time rescind the designation of any such transfer
agent or approve a change in the location through which any such transfer agent
acts, except that we will be required to maintain a transfer agent in each place
of payment for such series. We may at any time designate additional transfer
agents for any series of debt securities.

    Neither we nor any trustee shall be required to:

    - issue, register the transfer of or exchange debt securities of any series
      during a period beginning at the opening of business 15 days before the
      day that the notice of redemption of any debt securities selected for
      redemption is mailed and ending at the close of business on the day of
      such mailing;

    - register the transfer of or exchange any debt security, or portion
      thereof, so selected for redemption, in whole or in part, except the
      unredeemed portion of any debt security being redeemed in part; and

    - issue, register the transfer of or exchange any debt security that has
      been surrendered for repayment at the option of the holder, except the
      portion, if any, of such debt security not to be so repaid.

MERGER, CONSOLIDATION OR SALE OF ASSETS

    The indentures provide that we may, without the consent of the holders of
any outstanding debt securities, (1) consolidate with, (2) sell, lease or convey
all or substantially all of our assets to, or (3) merge with or into, any other
entity provided that:

    - either we are the continuing entity, or the successor entity, if other
      than us, assumes our obligations (A) to pay the principal of, and any
      premium (or make-whole amount) and interest on, all of the debt securities
      and (B) to duly perform and observe all of our covenants and conditions
      contained in each indenture;

    - immediately after giving effect to the transaction and treating any
      indebtedness that becomes our obligation or the obligation of any of our
      subsidiaries as having been incurred by us or by such subsidiary at the
      time of the transaction, no event of default under the indentures, and no
      event which, after notice or the lapse of time, or both, would become such
      an event of default, occurs and continues; and

                                       8

    - an officers' certificate and legal opinion covering such conditions are
      delivered to each trustee.

COVENANTS

    EXISTENCE.  Except as permitted under "Description of the Debt
Securities--Merger, consolidation or sale of assets," the indentures require us
to do or cause to be done all things necessary to preserve and keep in full
force and effect our existence, rights and franchises. However, the indentures
do not require us to preserve any right or franchise if we determine that any
right or franchise is no longer desirable in the conduct of our business.

    PAYMENT OF TAXES AND OTHER CLAIMS.  The indentures require us to pay,
discharge or cause to be paid or discharged, before they become delinquent all
taxes, assessments and governmental charges levied or imposed on us, our
Affiliates or our Affiliates' income, profits or property. However, we will not
be required to pay, discharge or cause to be paid or discharged any such tax,
assessment, charge or claim whose amount, applicability or validity is being
contested in good faith by appropriate proceedings.

    PROVISION OF FINANCIAL INFORMATION.  The indentures require us, within
15 days of each of the respective dates by which we are required to file annual
reports, quarterly reports and other documents with the SEC, (1) to mail to all
holders of debt securities, as their names and addresses appear in the
applicable register for such debt securities, without cost to such holders,
copies of the annual reports, quarterly reports and other documents that we file
with the SEC under Section 13 or Section 15(d) of the Exchange Act, and (2) to
supply, promptly upon written request and payment of the reasonable cost of
duplication and delivery, copies of such documents to any prospective holder.

    ADDITIONAL COVENANTS.  The applicable prospectus supplement will set forth
any additional covenants of Affiliated Managers Group relating to any series of
debt securities.

EVENTS OF DEFAULT, NOTICE AND WAIVER

    Unless the applicable prospectus supplement states otherwise, when we refer
to "events of default" as defined in the indentures with respect to any series
of debt securities, we mean:

    - default in the payment of any installment of interest on any debt security
      of such series continuing for 30 days;

    - default in the payment of principal of, or any premium (or make-whole
      amount) on, any debt security of such series at its maturity;

    - default in making any sinking fund payment as required for any debt
      security of such series;

    - default in the performance or breach of any other covenant or warranty of
      Affiliated Managers Group contained in the indenture continuing for
      60 days after written notice to us as provided in the applicable
      indenture;

    - (1) a default under any bond, debenture or note having an aggregate
      principal amount of at least $30,000,000; or

     (2) a default under any indenture or instrument under which there may be
     issued, secured or evidenced any existing or later created indebtedness for
     money borrowed by us or our Affiliates in an aggregate principal amount of
     at least $30,000,000,

     if the default results in the indebtedness becoming or being declared due
     and payable prior to the date it otherwise would have, without such
     indebtedness having been discharged, or such acceleration having been
     rescinded or annulled, within 30 days after notice to us specifying such
     default;

                                       9

    - bankruptcy, insolvency or reorganization, or court appointment of a
      receiver, liquidator or trustee of Affiliated Managers Group or any of our
      Affiliates which is considered a significant subsidiary; and

    - any other event of default provided with respect to a particular series of
      debt securities.

    When we use the term "significant subsidiary," we refer to the meaning
ascribed to such term in Rule 1-02 of Regulation S-X promulgated under the
Securities Act.

    If an event of default occurs and is continuing with respect to debt
securities of any series outstanding, then the applicable trustee or the holders
of 25% or more in principal amount of the debt securities of that series will
have the right to declare the principal amount of all the debt securities of
that series to be due and payable. If the debt securities of that series are
original issue discount securities or indexed securities, then the applicable
trustee or the holders of 25% or more in principal amount of the debt securities
of that series will have the right to declare the portion of the principal
amount as may be specified in the terms thereof to be due and payable. However,
at any time after such a declaration of acceleration has been made, but before a
judgment or decree for payment of the money due has been obtained by the
applicable trustee, the holders of at least a majority in principal amount of
outstanding debt securities of such series or of all debt securities then
outstanding under the applicable indenture may rescind and annul such
declaration and its consequences if:

    - we have deposited with the applicable trustee all required payments of the
      principal, any premium (or make-whole amount), and interest, plus
      applicable fees, expenses, disbursements and advances of the applicable
      trustee; and

    - all events of default, other than the non-payment of accelerated
      principal, or a specified portion thereof, and any premium (or make-whole
      amount), have been cured or waived.

    The indentures also provide that the holders of at least a majority in
principal amount of the outstanding debt securities of any series or of all debt
securities then outstanding under the applicable indenture may on behalf of all
holders waive any past default with respect to such series and its consequences,
except a default:

    - in the payment of the principal, any premium (or make-whole amount) or
      interest;

    - in respect of a covenant or provision contained in the applicable
      indenture that cannot be modified or amended without the consent of the
      holder of the outstanding debt security that is affected by the default;
      or

    - in respect of a covenant or provision for the benefit or protection of the
      trustee, without its express written consent.

    The indentures require each trustee to give notice to the holders of debt
securities within 90 days of a default unless such default has been cured or
waived. However, the trustee may withhold notice if specified responsible
officers of such trustee consider such withholding to be in the interest of the
holders of debt securities. The trustee may not withhold notice of a default in
the payment of principal, any premium or interest on any debt security of such
series or in the payment of any sinking fund installment in respect of any debt
security of such series.

    The indentures provide that holders of debt securities of any series may not
institute any proceedings, judicial or otherwise, with respect to such indenture
or for any remedy under the indenture, unless the trustee fails to act for a
period of 60 days after the trustee has received a written request to institute
proceedings in respect of an event of default from the holders of 25% or more in
principal amount of the outstanding debt securities of such series, as well as
an offer of indemnity reasonably satisfactory to the trustee. However, this
provision will not prevent any holder of debt

                                       10

securities from instituting suit for the enforcement of payment of the principal
of, and any premium (or make-whole amount) and interest on, such debt securities
at the respective due dates thereof.

    The indentures provide that, subject to provisions in each indenture
relating to its duties in the case of a default, a trustee has no obligation to
exercise any of its rights or powers at the request or direction of any holders
of any series of debt securities then outstanding under the indenture, unless
the holders have offered to the trustee reasonable security or indemnity. The
holders of at least a majority in principal amount of the outstanding debt
securities of any series or of all debt securities then outstanding under an
indenture shall have the right to direct the time, method and place of
conducting any proceeding for any remedy available to the applicable trustee, or
of exercising any trust or power conferred upon such trustee. However, a trustee
may refuse to follow any direction which:

    - is in conflict with any law or the applicable indenture;

    - may involve the trustee in personal liability; or

    - may be unduly prejudicial to the holders of debt securities of the series
      not joining the proceeding.

    Within 120 days after the close of each fiscal year, we will be required to
deliver to each trustee a certificate, signed by one of our several specified
officers stating whether or not that officer has knowledge of any default under
the applicable indenture. If the officer has knowledge of any default, the
notice must specify the nature and status of the default.

MODIFICATION OF THE INDENTURES

    The indentures provide that modifications and amendments may be made only
with the consent of the affected holders of at least a majority in principal
amount of all outstanding debt securities issued under that indenture. However,
no such modification or amendment may, without the consent of the holders of the
debt securities affected by the modification or amendment:

    - change the stated maturity of the principal of, or any premium (or
      make-whole amount) on, or any installment of principal of or interest on,
      any such debt security;

    - reduce the principal amount of, the rate or amount of interest on or any
      premium (or make-whole amount) payable on redemption of any such debt
      security;

    - reduce the amount of principal of an original issue discount security that
      would be due and payable upon declaration of acceleration of the maturity
      thereof or would be provable in bankruptcy, or adversely affect any right
      of repayment of the holder of any such debt security;

    - change the place of payment or the coin or currency for payment of
      principal of, or any premium (or make-whole amount) or interest on, any
      such debt security;

    - impair the right to institute suit for the enforcement of any payment on
      or with respect to any such debt security;

    - reduce the percentage in principal amount of any outstanding debt
      securities necessary to modify or amend the applicable indenture with
      respect to such debt securities, to waive compliance with particular
      provisions thereof or defaults and consequences thereunder or to reduce
      the quorum or voting requirements set forth in the applicable indenture;
      and

    - modify any of the foregoing provisions or any of the provisions relating
      to the waiver of particular past defaults or covenants, except to increase
      the required percentage to effect such action or to provide that some of
      the other provisions may not be modified or waived without the consent of
      the holder of such debt security.

                                       11

    The holders of a majority in aggregate principal amount of the outstanding
debt securities of each series may, on behalf of all holders of debt securities
of that series, waive, insofar as that series is concerned, our compliance with
material restrictive covenants of the applicable indenture.

    We and our respective trustee may make modifications and amendments of an
indenture without the consent of any holder of debt securities for any of the
following purposes:

    - to evidence the succession of another person to us as obligor under such
      indenture;

    - to add to our covenants for the benefit of the holders of all or any
      series of debt securities or to surrender any right or power conferred
      upon us in such indenture;

    - to add events of default for the benefit of the holders of all or any
      series of debt securities;

    - to add or change any provisions of an indenture (1) to facilitate the
      issuance of, or to change or eliminate restrictions on the payment of
      principal of, or premium (or make-whole amount) or interest on, debt
      securities in bearer form, or (2) to permit or facilitate the issuance of
      debt securities in uncertificated form, provided that such action shall
      not adversely affect the interests of the holders of the debt securities
      of any series in any material respect;

    - to change or eliminate any provisions of an indenture, provided that any
      such change or elimination shall become effective only when there are no
      debt securities outstanding of any series created prior thereto which are
      entitled to the benefit of such provision;

    - to secure the debt securities;

    - to establish the form or terms of debt securities of any series;

    - to provide for the acceptance of appointment by a successor trustee or
      facilitate the administration of the trusts under an indenture by more
      than one trustee;

    - to cure any ambiguity, defect or inconsistency in an indenture, provided
      that such action shall not adversely affect the interests of holders of
      debt securities of any series issued under such indenture; and

    - to supplement any of the provisions of an indenture to the extent
      necessary to permit or facilitate defeasance and discharge of any series
      of such debt securities, provided that such action shall not adversely
      affect the interests of the holders of the outstanding debt securities of
      any series.

VOTING

    The indentures provide that in determining whether the holders of the
requisite principal amount of outstanding debt securities of a series have given
any request, demand, authorization, direction, notice, consent or waiver under
the indentures or whether a quorum is present at a meeting of holders of debt
securities:

    - the principal amount of an original issue discount security that shall be
      deemed to be outstanding shall be the amount of the principal thereof that
      would be due and payable as of the date of such determination upon
      declaration of acceleration of the maturity thereof;

    - the principal amount of any debt security denominated in a foreign
      currency that shall be deemed outstanding shall be the United States
      dollar equivalent, determined on the issue date for such debt security, of
      the principal amount or, in the case of an original issue discount
      security, the United States dollar equivalent on the issue date of such
      debt security of the amount determined as provided in the preceding bullet
      point;

                                       12

    - the principal amount of an indexed security that shall be deemed
      outstanding shall be the principal face amount of such indexed security at
      original issuance, unless otherwise provided for such indexed security
      under such indenture; and

    - debt securities owned by us or any other obligor upon the debt securities
      or by any affiliate of ours or of such other obligor shall be disregarded.

    The indentures contain provisions for convening meetings of the holders of
debt securities of a series. A meeting will be permitted to be called at any
time by the applicable trustee, and also, upon request, by us or the holders of
at least 25% in principal amount of the outstanding debt securities of such
series, in any such case upon notice given as provided in such indenture. Except
for any consent that must be given by the holder of each debt security affected
by the modifications and amendments of an indenture described above, any
resolution presented at a meeting or adjourned meeting duly reconvened at which
a quorum is present may be adopted by the affirmative vote of the holders of a
majority of the aggregate principal amount of the outstanding debt securities of
that series represented at such meeting.

    Notwithstanding the preceding paragraph, except as referred to above, any
resolution relating to a request, demand, authorization, direction, notice,
consent, waiver or other action that may be made, given or taken by the holders
of a specified percentage, which is less than a majority, of the aggregate
principal amount of the outstanding debt securities of a series may be adopted
at a meeting or adjourned meeting duly reconvened at which a quorum is present
by the affirmative vote of such specified percentage.

    Any resolution passed or decision taken at any properly held meeting of
holders of debt securities of any series will be binding on all holders of such
series. The quorum at any meeting called to adopt a resolution, and at any
reconvened meeting, will be persons holding or representing a majority in
principal amount of the outstanding debt securities of a series. However, if any
action is to be taken relating to a consent or waiver which may be given by the
holders of at least a specified percentage in principal amount of the
outstanding debt securities of a series, the persons holding such percentage
will constitute a quorum.

    Notwithstanding the foregoing provisions, the indentures provide that if any
action is to be taken at a meeting with respect to any request, demand,
authorization, direction, notice, consent, waiver and other action that such
indenture expressly provides may be made, given or taken by the holders of a
specified percentage in principal amount of all outstanding debt securities
affected by such action, or of the holders of such series and one or more
additional series:

    - there shall be no minimum quorum requirement for such meeting; and

    - the principal amount of the outstanding debt securities of such series
      that vote in favor of such request, demand, authorization, direction,
      notice, consent, waiver or other action shall be taken into account in
      determining whether such request, demand, authorization, direction,
      notice, consent, waiver or other action has been made, given or taken
      under such indenture.

SUBORDINATION

    Unless otherwise provided in the applicable prospectus supplement,
subordinated securities will be subject to the following subordination
provisions.

    Upon any distribution to our creditors in a liquidation, dissolution or
reorganization, the payment of the principal of and interest on any subordinated
securities will be subordinated to the extent provided in the applicable
indenture in right of payment to the prior payment in full of all senior debt.
However, our obligation to make payments of the principal of and interest on
such subordinated securities otherwise will not be affected. No payment of
principal or interest will be permitted to be

                                       13

made on subordinated securities at any time if a default on senior debt exists
that permits the holders of such senior debt to accelerate its maturity and the
default is the subject of judicial proceedings or we receive notice of the
default. After all senior debt is paid in full and until the subordinated
securities are paid in full, holders of subordinated securities will be
subrogated to the rights of holders of senior debt to the extent that
distributions otherwise payable to holders of subordinated securities have been
applied to the payment of senior debt. The subordinated indenture will not
restrict the amount of senior debt or other indebtedness of Affiliated Managers
Group and our subsidiaries. As a result of these subordination provisions, in
the event of a distribution of assets upon insolvency, holders of subordinated
securities may recover less, ratably, than our general creditors.

    "Senior Debt" will be defined in the applicable indenture as the principal
of and interest on, or substantially similar payments to be made by us in
respect of, the following, whether outstanding at the date of execution of the
applicable indenture or subsequently incurred, created or assumed:

    - indebtedness incurred by us for money borrowed or represented by
      purchase-money obligations;

    - indebtedness incurred by us evidenced by notes, debentures, bonds, or
      other securities issued under the provisions of an indenture, fiscal
      agency agreement or other agreement;

    - our obligations as lessee under leases of property either made as part of
      any sale and leaseback transaction to which we are a party or otherwise;

    - indebtedness of partnerships and joint ventures which is included in our
      consolidated financial statements;

    - indebtedness, obligations and liabilities of others in respect of which we
      are liable contingently or otherwise to pay or advance money or property
      or as guarantor, endorser or otherwise or which we have agreed to purchase
      or otherwise acquire; and

    - any binding commitment we have to fund any real estate investment or to
      fund any investment in any entity making such real estate investment.

    In each case, the following will not be Senior Debt:

    - any such indebtedness, obligation or liability referred to in the
      preceding clauses (1) that is outstanding and (2) the instrument creating
      or evidencing such indebtedness, obligation or liability provides that the
      same is not superior to or ranks on an equal basis with the subordinated
      securities with respect to right of payment;

    - any such indebtedness, obligation or liability that is subordinated to
      indebtedness incurred by us to substantially the same extent as or to a
      greater extent than the subordinated securities are subordinated; and

    - the subordinated securities.

    No restrictions will be included in any indenture relating to subordinated
securities upon the creation of additional senior debt.

    If this prospectus is being delivered in connection with the offering of a
series of subordinated securities, the accompanying prospectus supplement or the
information incorporated in this prospectus by reference will set forth the
approximate amount of senior debt outstanding as of the end of our most recent
fiscal quarter.

                                       14

DISCHARGE, DEFEASANCE AND COVENANT DEFEASANCE

    Unless otherwise indicated in the applicable prospectus supplement, the
indentures allow us to discharge our obligations to holders of any series of
debt securities issued under any indenture when:

    - either (1) all securities of such series have already been delivered to
      the applicable trustee for cancellation; or (2) all securities of such
      series have not already been delivered to the applicable trustee for
      cancellation but (a) have become due and payable, (b) will become due and
      payable within one year, or (c) if redeemable at our option, are to be
      redeemed within one year, and we have irrevocably deposited with the
      applicable trustee, in trust, funds in such currency or currencies,
      currency unit or units or composite currency or currencies in which such
      debt securities are payable, an amount sufficient to pay the entire
      indebtedness on such debt securities in respect of principal and any
      premium (or make-whole amount) and interest to the date of such deposit if
      such debt securities have become due and payable or, if they have not, to
      the stated maturity or redemption date;

    - we have paid or caused to be paid all other sums payable; and

    - we have delivered to the trustee an officers' certificate and an opinion
      of counsel stating the conditions to discharging the debt securities have
      been satisfied.

    Unless otherwise indicated in the applicable prospectus supplement, the
indentures provide that, upon our irrevocable deposit with the applicable
trustee, in trust, of an amount, in such currency or currencies, currency unit
or units or composite currency or currencies in which such debt securities are
payable at stated maturity, or government obligations, or both, applicable to
such debt securities, which through the scheduled payment of principal and
interest in accordance with their terms will provide money in an amount
sufficient to pay the principal of, and any premium (or make-whole amount) and
interest on, such debt securities, and any mandatory sinking fund or analogous
payments thereon, on the scheduled due dates therefor, we may elect either:

    - to defease and be discharged from any and all obligations with respect to
      such debt securities; or

    - to be released from our obligations with respect to such debt securities
      under the applicable indenture or, if provided in the applicable
      prospectus supplement, our obligations with respect to any other covenant,
      and any omission to comply with such obligations shall not constitute an
      event of default with respect to such debt securities.

    Notwithstanding the above, we may not elect to defease and be discharged
from the obligation to pay any additional amounts upon the occurrence of
particular events of tax, assessment or governmental charge with respect to
payments on such debt securities and the obligations to register the transfer or
exchange of such debt securities, to replace temporary or mutilated, destroyed,
lost or stolen debt securities, to maintain an office or agency in respect of
such debt securities, or to hold monies for payment in trust.

    The indentures only permit us to establish the trust described in the
paragraph above if, among other things, we have delivered to the applicable
trustee an opinion of counsel to the effect that the holders of such debt
securities will not recognize income, gain or loss for federal income tax
purposes as a result of such defeasance or covenant defeasance and will be
subject to federal income tax on the same amounts, in the same manner and at the
same times as would have been the case if such defeasance or covenant defeasance
had not occurred. Such opinion of counsel, in the case of defeasance, will be
required to refer to and be based upon a ruling received from or published by
the Internal Revenue Service or a change in applicable federal income tax law
occurring after the date of the indenture. In the event of such defeasance, the
holders of such debt securities would be able to look only to such trust fund
for payment of principal, any premium (or make-whole amount), and interest.

                                       15

    When we use the term "government obligations," we mean securities that are:

    - direct obligations of the United States or the government that issued the
      foreign currency in which the debt securities of a particular series are
      payable, for the payment of which its full faith and credit is pledged; or

    - obligations of a person controlled or supervised by and acting as an
      agency or instrumentality of the United States or other government that
      issued the foreign currency in which the debt securities of such series
      are payable, the payment of which is unconditionally guaranteed as a full
      faith and credit obligation by the United States or such other government,
      which are not callable or redeemable at the option of the issuer thereof
      and shall also include a depository receipt issued by a bank or trust
      company as custodian with respect to any such government obligation or a
      specific payment of interest on or principal of any such government
      obligation held by such custodian for the account of the holder of a
      depository receipt. However, except as required by law, such custodian is
      not authorized to make any deduction from the amount payable to the holder
      of such depository receipt from any amount received by the custodian in
      respect of the government obligation or the specific payment of interest
      on or principal of the government obligation evidenced by such depository
      receipt.

    Unless otherwise provided in the applicable prospectus supplement, if after
we have deposited funds and/or government obligations to effect defeasance or
covenant defeasance with respect to debt securities of any series, (a) the
holder of a debt security of such series is entitled to, and does, elect under
the terms of the applicable indenture or the terms of such debt security to
receive payment in a currency, currency unit or composite currency other than
that in which such deposit has been made in respect of such debt security, or
(b) a conversion event occurs in respect of the currency, currency unit or
composite currency in which such deposit has been made, the indebtedness
represented by such debt security will be deemed to have been, and will be,
fully discharged and satisfied through the payment of the principal of, and
premium (or make-whole amount) and interest on, such debt security as they
become due out of the proceeds yielded by converting the amount so deposited in
respect of such debt security into the currency, currency unit or composite
currency in which such debt security becomes payable as a result of such
election or such cessation of usage based on the applicable market exchange
rate.

    When we use the term "conversion event," we mean the cessation of use of:

    - a currency, currency unit or composite currency both by the government of
      the country that issued such currency and for the settlement of
      transactions by a central bank or other public institutions of or within
      the international banking community;

    - the European Currency Unit both within the European Monetary System and
      for the settlement of transactions by public institutions of or within the
      European Communities; or

    - any currency unit or composite currency other than the European Currency
      Unit for the purposes for which it was established.

    Unless otherwise provided in the applicable prospectus supplement, all
payments of principal of, and any premium (or make-whole amount) and interest
on, any debt security that is payable in a foreign currency that ceases to be
used by its government of issuance shall be made in United States dollars.

    In the event that (a) we effect covenant defeasance with respect to any debt
securities and (b) such debt securities are declared due and payable because of
the occurrence of any event of default, the amount in such currency, currency
unit or composite currency in which such debt securities are payable, and
government obligations on deposit with the applicable trustee, will be
sufficient to pay amounts due on such debt securities at the time of their
stated maturity but may not be sufficient to pay

                                       16

amounts due on such debt securities at the time of the acceleration resulting
from such event of default. However, we would remain liable to make payments of
such amounts due at the time of acceleration. Notwithstanding the first sentence
of this paragraph, events of default in (b) above shall not include the event of
default described in (1) the fourth bullet point under "Description of the Debt
Securities--Events of default, notice and waiver" with respect to specified
sections of an indenture or (2) the seventh bullet point under "Description of
the Debt Securities--Events of default, notice and waiver" with respect to any
other covenant as to which there has been covenant defeasance.

    The applicable prospectus supplement may further describe the provisions, if
any, permitting such defeasance or covenant defeasance, including any
modifications to the provisions described above, with respect to the debt
securities of or within a particular series.

CONVERSION RIGHTS

    The terms and conditions, if any, upon which the debt securities are
convertible into common stock or preferred stock will be set forth in the
applicable prospectus supplement. The terms will include whether the debt
securities are convertible into shares of common stock or preferred stock, the
conversion price (or manner of calculation thereof), the conversion period,
provisions as to whether conversion will be at our option or the option of the
holders, the events requiring an adjustment of the conversion price and
provisions affecting conversion in the event of the redemption of the debt
securities and any restrictions on conversion.

GLOBAL SECURITIES

    The debt securities of a series may be issued in whole or in part in the
form of one or more global securities that will be deposited with, or on behalf
of, a depository identified in the applicable prospectus supplement relating to
such series. Global securities, if any, issued in the United States are expected
to be deposited with The Depository Trust Company, or DTC, as depository. We may
issue global securities in either registered or bearer form and in either
temporary or permanent form. We will describe the specific terms of the
depository arrangement with respect to a series of debt securities in the
applicable prospectus supplement relating to such series. We expect that unless
the applicable prospectus supplement provides otherwise, the following
provisions will apply to depository arrangements.

    Once a global security is issued, the depository for such global security or
its nominee will credit on its book-entry registration and transfer system the
respective principal amounts of the individual debt securities represented by
such global security to the accounts of participants that have accounts with
such depository. Such accounts shall be designated by the underwriters, dealers
or agents with respect to such debt securities or by us if we offer such debt
securities directly. Ownership of beneficial interests in such global security
will be limited to participants with the depository or persons that may hold
interests through those participants.

    We expect that, under procedures established by DTC, ownership of beneficial
interests in any global security for which DTC is the depository will be shown
on, and the transfer of that ownership will be effected only through, records
maintained by DTC or its nominee (with respect to beneficial interests of
participants with the depository) and records of participants (with respect to
beneficial interests of persons who hold through participants with the
depository). Neither we nor the trustee will have any responsibility or
liability for any aspect of the records of DTC or for maintaining, supervising
or reviewing any records of DTC or any of its participants relating to
beneficial ownership interests in the debt securities. The laws of some states
require that certain purchasers of securities take physical delivery of such
securities in definitive form. Such limits and laws may impair the ability to
own, pledge or transfer beneficial interest in a global security.

                                       17

    So long as the depository for a global security or its nominee is the
registered owner of such global security, such depository or such nominee, as
the case may be, will be considered the sole owner or holder of the debt
securities represented by the global security for all purposes under the
applicable indenture. Except as described below or in the applicable prospectus
supplement, owners of beneficial interest in a global security will not be
entitled to have any of the individual debt securities represented by such
global security registered in their names, will not receive or be entitled to
receive physical delivery of any such debt securities in definitive form and
will not be considered the owners or holders thereof under the applicable
indenture. Beneficial owners of debt securities evidenced by a global security
will not be considered the owners or holders thereof under the applicable
indenture for any purpose, including with respect to the giving of any
direction, instructions or approvals to the trustee under the indenture.
Accordingly, each person owning a beneficial interest in a global security with
respect to which DTC is the depository must rely on the procedures of DTC and,
if such person is not a participant with the depository, on the procedures of
the participant through which such person owns its interests, to exercise any
rights of a holder under the applicable indenture. We understand that, under
existing industry practice, if DTC requests any action of holders or if an owner
of a beneficial interest in a global security desires to give or take any action
which a holder is entitled to give or take under the applicable indenture, DTC
would authorize the participants holding the relevant beneficial interest to
give or take such action, and such participants would authorize beneficial
owners through such participants to give or take such actions or would otherwise
act upon the instructions of beneficial owners holding through them.

    Payments of principal of, and any premium (or make-whole amount) and
interest on, individual debt securities represented by a global security
registered in the name of a depository or its nominee will be made to or at the
direction of the depository or its nominee, as the case may be, as the
registered owner of the global security under the applicable indenture. Under
the terms of the applicable indenture, we and the trustee may treat the persons
in whose name debt securities, including a global security, are registered as
the owners thereof for the purpose of receiving such payments. Consequently,
neither we nor the trustee have or will have any responsibility or liability for
the payment of such amounts to beneficial owners of debt securities including
principal, any premium (or make-whole amount) or interest. We believe, however,
that it is currently the policy of DTC to immediately credit the accounts of
relevant participants with such payments, in amounts proportionate to their
respective holdings of beneficial interests in the relevant global security as
shown on the records of DTC or its nominee. We also expect that payments by
participants to owners of beneficial interests in such global security held
through such participants will be governed by standing instructions and
customary practices, as is the case with securities held for the account of
customers in bearer form or registered in street name, and will be the
responsibility of such participants. Redemption notices with respect to any debt
securities represented by a global security will be sent to the depository or
its nominee. If less than all of the debt securities of any series are to be
redeemed, we expect the depository to determine the amount of the interest of
each participant in such debt securities to be redeemed to be determined by lot.
Neither we, the trustee, any paying agent nor the security registrar for such
debt securities will have any responsibility or liability for any aspect of the
records relating to or payments made on account of beneficial ownership
interests in the global security for such debt securities or for maintaining any
records with respect thereto.

    Neither we nor the trustee will be liable for any delay by the holders of a
global security or the depository in identifying the beneficial owners of debt
securities, and we and the trustee may conclusively rely on, and will be
protected in relying on, instructions from the holder of a global security or
the depository for all purposes. The rules applicable to DTC and its
participants are on file with the SEC.

    If a depository for any debt securities is at any time unwilling, unable or
ineligible to continue as depository and we do not appoint a successor
depository within 90 days, we will issue individual debt

                                       18

securities in exchange for the global security representing such debt
securities. In addition, we may at any time and in our sole discretion, subject
to any limitations described in the prospectus supplement relating to such debt
securities, determine not to have any of such debt securities represented by one
or more global securities and in such event will issue individual debt
securities in exchange for the global security or securities representing such
debt securities. Individual debt securities so issued will be issued in
denominations of $1,000 and integral multiples of $1,000.

    The debt securities of a series may also be issued in whole or in part in
the form of one or more bearer global securities that will be deposited with a
depository, or with a nominee for such depository, identified in the applicable
prospectus supplement. Any such bearer global securities may be issued in
temporary or permanent form. The specific terms and procedures, including the
specific terms of the depository arrangement, with respect to any portion of a
series of debt securities to be represented by one or more bearer global
securities will be described in the applicable prospectus supplement.

NO RECOURSE

    There is no recourse under any obligation, covenant or agreement in the
applicable indenture or with respect to any security against any of our or our
successor's past, present or future stockholders, employees, officers or
directors.

                         DESCRIPTION OF PREFERRED STOCK

    The following is a description of the material terms and provisions of our
preferred stock. It may not contain all of the information that is important to
you. Therefore, you should read our charter and bylaws before you purchase any
shares of our preferred stock.

GENERAL

    Under our charter, we are authorized to issue 5,000,000 shares of preferred
stock, par value $.01 per share, all of which is currently undesignated. As of
December 3, 2001, no shares of preferred stock were issued and outstanding.

    Shares of preferred stock may be issued from time to time, in one or more
series, as authorized by our board of directors. Prior to the issuance of shares
of each series, the board of directors is required by the Delaware General
Corporation Law and our charter to fix, for each series, the designations,
powers and preferences and the relative, participating, optional or other
special rights of the shares of each series and any qualifications, limitations
and restrictions thereof, as are permitted by Delaware law. Our board of
directors could authorize the issuance of shares of preferred stock with terms
and conditions that could have the effect of discouraging a takeover or other
transactions that holders of common stock might believe to be in their best
interests or in which holders of some, or a majority, of the shares of common
stock might receive a premium for their shares over the then market price of
such shares of common stock.

TERMS

    You should refer to the prospectus supplement relating to the offering of a
series of preferred stock for the specific terms of that series, including:

    - the distinctive serial designation and the number of shares constituting
      such series;

    - the dividend rates or the amount of dividends to be paid on the shares of
      such series, whether dividends shall be cumulative and, if so, from which
      date or dates, the payment date or dates for dividends, and the
      participating and other rights, if any, with respect to dividends;

    - the voting powers, full or limited, if any, of the shares of such series;

                                       19

    - whether the shares of such series shall be redeemable and, if so, the
      price or prices at which, and the terms and conditions on which, such
      shares may be redeemed;

    - the amount or amounts payable upon the shares of such series and any
      preferences applicable thereto in the event of voluntary or involuntary
      liquidation, dissolution or winding up of the company;

    - whether the shares of such series shall be entitled to the benefit of a
      sinking or retirement fund to be applied to the purchase or redemption of
      such shares, and if so entitled, the amount of such fund and the manner of
      its application, including the price or prices at which such shares may be
      redeemed or purchased through the application of such fund;

    - whether the shares of such series shall be convertible into, or
      exchangeable for, shares of any other class or classes or of any other
      series of the same or any other class or classes of stock of the company
      and, if so convertible or exchangeable, the conversion price or prices, or
      the rate or rates of exchange, and the adjustments thereof, if any, at
      which such conversion or exchange may be made, and any other terms and
      conditions of such conversion or exchange;

    - the price or other consideration for which the shares of such series shall
      be issued;

    - whether the shares of such series which are redeemed or converted shall
      have the status of authorized but unissued shares of undesignated
      preferred stock (or series thereof) and whether such shares may be
      reissued as shares of the same or any other class or series of stock; and

    - such other powers, preferences, rights, qualifications, limitations and
      restrictions thereof as the board of directors may deem advisable.

RANK

    Unless otherwise specified in the applicable prospectus supplement, the
preferred stock will, with respect to dividend rights and rights upon a
liquidation, dissolution or winding up of our affairs, rank:

    - senior to all classes or series of our common stock, and to all equity
      securities ranking junior to such preferred stock with respect to dividend
      rights or rights upon liquidation, dissolution or winding up of our
      affairs;

    - on parity with all equity securities issued by us, the terms of which
      specifically provide that such equity securities rank on parity with the
      preferred stock with respect to dividend rights or rights upon
      liquidation, dissolution or winding up of our affairs; and

    - junior to all equity securities issued by us, the terms of which
      specifically provide that such equity securities rank senior to the
      preferred stock with respect to dividend rights or rights upon
      liquidation, dissolution or winding up of our affairs.

    The term "equity securities" does not include convertible debt securities.

DIVIDENDS

    Holders of the preferred stock of each series will be entitled to receive
cash dividends when, as and if declared by our board of directors. We will pay
dividends out of assets that are legally available for payment of dividends. We
will specify the rate(s) of dividends and the dates that we will pay dividends
in the applicable prospectus supplement. Dividends will be payable to holders of
record as they appear on our stock transfer books on such record dates as fixed
by our board of directors.

    Dividends on any series of the preferred stock may be cumulative or
non-cumulative, as provided in the applicable prospectus supplement. Dividends,
if cumulative, will be cumulative from and after the date set forth in the
applicable prospectus supplement. If our board of directors fails to declare a

                                       20

dividend payable on a dividend payment date on any series of the preferred stock
for which dividends are non-cumulative, then the holders of that series of the
preferred stock will have no right to receive a dividend in respect of the
dividend period ending on that dividend payment date. Accordingly, we will have
no obligation to pay the dividend accrued for that period, whether or not
dividends on that series are declared payable on any future dividend payment
date.

    If preferred stock of any series is outstanding, we will not declare, pay or
set aside funds to pay dividends on any other series of our capital stock
ranking, as to dividends, on parity with or junior to the preferred stock of
such series for any period unless:

    - if that series of preferred stock has a cumulative dividend, we have
      declared and paid or contemporaneously declare and pay or set aside funds
      to pay full cumulative dividends on the preferred stock of such series for
      all past dividend periods and the then current dividend period; or

    - if that series of preferred stock does not have a cumulative dividend, we
      have declared and paid or contemporaneously declare and pay or set aside
      funds to pay full dividends on the preferred stock of such series for the
      then current dividend period.

    We must declare all dividends pro rata on all series of preferred stock that
rank on parity with the series of preferred stock upon which we paid dividends
if we did not pay or set aside funds to pay dividends on the series of preferred
stock in full. We must declare dividends pro rata to ensure that the amount of
dividends declared per share of preferred stock bears in all cases the same
ratio that accrued dividends per share of preferred stock bears to each other.
We will not accumulate unpaid dividends for prior dividend periods with respect
to accrued dividends on preferred stock that does not have cumulative dividends.
No interest, or sum of money in lieu of interest, will be payable in respect of
any payments that may be in arrears.

    Except as provided in the immediately preceding paragraph, unless:

    - such series of preferred stock has a cumulative dividend, and we have
      declared and paid or contemporaneously declare and pay or set aside funds
      to pay full cumulative dividends for all past dividend periods and the
      then current dividend period; or

    - such series of preferred stock does not have a cumulative dividend, and we
      have declared and paid or contemporaneously declare and pay or set aside
      funds to pay full dividends for the then current dividend period,

we will not: (1) declare, pay or set aside funds to pay dividends or declare or
make any other distribution upon the common stock or any other shares of our
stock ranking junior to or on parity with the preferred stock of such series as
to dividends or upon liquidation; (2) redeem, purchase or otherwise acquire for
any consideration any common stock, or any other shares of our stock ranking
junior to or on parity with the preferred stock of such series as to dividends;
nor (3) pay any monies to or make any monies available for a sinking fund to
redeem any such shares, except by conversion into or exchange for other shares
of our capital stock ranking junior to the preferred stock of such series as to
dividends or liquidation. Notwithstanding the preceding sentence, we may declare
or set aside dividends in common stock or other shares of capital stock ranking
junior to the preferred stock of such series as to dividends and upon
liquidation.

    Any dividend payment we make on a series of preferred stock shall first be
credited against the earliest accrued but unpaid dividend due with respect to
shares of such series which remains payable.

                                       21

REDEMPTION

    If so provided in the applicable prospectus supplement, the preferred stock
will be subject to mandatory redemption or redemption at our option, in whole or
in part, upon the terms, at the times and at the redemption prices set forth in
such prospectus supplement.

    The prospectus supplement relating to a series of preferred stock that is
subject to mandatory redemption will specify the number of shares that will be
redeemed in each year commencing after a specified date at a specified
redemption price per share, together with an amount equal to all accrued and
unpaid dividends thereon to the date of redemption. Unless the shares have a
cumulative dividend, such accrued dividends will not include any accumulation in
respect of unpaid dividends for prior dividend periods. We may pay the
redemption price in cash or other property, as specified in the applicable
prospectus supplement. If the redemption price for preferred stock of any series
is payable only from the net proceeds of the issuance of shares of our capital
stock, the terms of such preferred stock may provide that, if no such shares of
our capital stock have been issued or to the extent the net proceeds from any
issuance are insufficient to pay in full the aggregate redemption price then
due, such preferred stock will automatically and mandatorily convert into the
applicable shares of our capital stock under the conversion provisions specified
in the applicable prospectus supplement.

    Notwithstanding the foregoing, we will not redeem any preferred stock of a
series unless:

    - if that series of preferred stock has a cumulative dividend, we have
      declared and paid or contemporaneously declare and pay or set aside funds
      to pay full cumulative dividends on the preferred stock for the past and
      current dividend periods; or

    - if that series of preferred stock does not have a cumulative dividend, we
      have declared and paid or contemporaneously declare and pay or set aside
      funds to pay full dividends on the preferred stock for the current
      dividend period.

    However, in no case will we redeem any preferred stock of a series unless we
redeem all outstanding preferred stock of such series simultaneously.

    In addition, we will not acquire any preferred stock of a series unless:

    - if that series of preferred stock has a cumulative dividend, we have
      declared and paid or contemporaneously declare and pay or set aside funds
      to pay full cumulative dividends on all outstanding shares of such series
      of preferred stock for all past dividend periods and the then current
      dividend period; or

    - if that series of preferred stock does not have a cumulative dividend, we
      have declared and paid or contemporaneously declare and pay or set aside
      funds to pay full dividends on the preferred stock of such series for the
      then current dividend period.

    However, at any time we may purchase or acquire preferred stock of that
series (1) in accordance with a purchase or exchange offer made on the same
terms to holders of all outstanding preferred stock of such series or (2) by
conversion into or exchange for shares of our capital stock ranking junior to
the preferred stock of such series as to dividends and upon liquidation.

    If fewer than all of the outstanding shares of preferred stock of any series
are to be redeemed, we will determine the number of shares that may be redeemed
pro rata from the holders of record of such shares in proportion to the number
of such shares held or for which redemption is requested by such holder or by
any other equitable manner that we determine. Such determination will reflect
adjustments to avoid redemption of fractional shares.

                                       22

    We will mail notice of redemption at least 30 days but not more than
60 days before the redemption date to each holder of record of preferred stock
to be redeemed at the address shown on our stock transfer books. Each notice
shall state:

    - the redemption date;

    - the number of shares and series to be redeemed;

    - the redemption price;

    - the place or places where certificates are to be surrendered for payment
      of the redemption price;

    - that dividends on the shares to be redeemed will cease to accrue on such
      redemption date;

    - the date upon which the holder's conversion rights, if any, as to such
      shares shall terminate; and

    - the specific number of shares to be redeemed from each such holder if
      fewer than all the shares of any series are to be redeemed.

    If notice of redemption has been given and we have set aside the funds
necessary for such redemption in trust for the benefit of the holders of any
shares so called for redemption, then from and after the redemption date,
dividends will cease to accrue on such shares, and all rights of the holders of
such shares will terminate, except the right to receive the redemption price.

LIQUIDATION PREFERENCE

    Upon any voluntary or involuntary liquidation, dissolution or winding up of
our affairs, then, before we make any distribution or payment to the holders of
any common stock or any other class or series of our capital stock ranking
junior to the preferred stock in the distribution of assets upon any
liquidation, dissolution or winding up of our affairs, the holders of each
series of preferred stock will be entitled to receive, out of assets legally
available for distribution to stockholders, liquidating distributions in the
amount of the liquidation preference per share set forth in the applicable
prospectus supplement, plus any accrued and unpaid dividends thereon. Such
dividends will not include any accumulation in respect of unpaid noncumulative
dividends for prior dividend periods. After full payment of their liquidating
distributions, holders will have no right or claim to any of our remaining
assets. Upon any such voluntary or involuntary liquidation, dissolution or
winding up, if our available assets are insufficient to pay the amount of the
liquidating distributions on all outstanding preferred stock and the
corresponding amounts payable on all other classes or series of our capital
stock ranking on parity with the preferred stock in the distribution of assets,
then the holders of the preferred stock and all other such classes or series of
capital stock will share ratably in any such distribution of assets in
proportion to the full liquidating distributions to which they would otherwise
be entitled.

    Upon liquidation, dissolution or winding up and if we have made liquidating
distributions in full to all holders of preferred stock, we will distribute our
remaining assets among the holders of any other classes or series of capital
stock ranking junior to the preferred stock according to their respective rights
and preferences and, in each case, according to their respective number of
shares. For such purposes, our consolidation or merger with or into any other
corporation, trust or entity, or the sale, lease or conveyance of all or
substantially all of our assets or business will not be deemed to constitute a
liquidation, dissolution or winding up of our affairs.

                                       23

VOTING RIGHTS

    Holders of preferred stock will have no voting rights, except as described
in the next paragraph, as otherwise from time to time required by law or as
indicated in the applicable prospectus supplement.

    Unless otherwise provided for any series of preferred stock, so long as any
preferred stock of a series remains outstanding, we will not, without the
affirmative vote or consent of the holders of at least two-thirds of the
preferred stock of such series outstanding at the time, given in person or by
proxy, either in writing or at a meeting with each of such series voting
separately as a class:

    - authorize or create, or increase the authorized or issued amount of, any
      class or series of shares of capital stock ranking senior to such series
      of preferred stock with respect to payment of dividends or the
      distribution of assets upon liquidation, dissolution or winding up, or
      reclassify any of our authorized shares of capital stock into such shares,
      or create, authorize or issue any obligation or security convertible into
      or evidencing the right to purchase any such shares; or

    - amend, alter or repeal the provisions of our charter or the amendment to
      our charter designating the terms for such series of preferred stock,
      whether by merger, consolidation or otherwise, so as to materially and
      adversely affect any right, preference, privilege or voting power of such
      series of preferred stock or the holders thereof.

Notwithstanding the preceding bullet point, if the preferred stock remains
outstanding with the terms thereof materially unchanged, the occurrence of any
of the events described above shall not be deemed to materially and adversely
affect the rights, preferences, privileges or voting power of holders of
preferred stock, even if upon the occurrence of such an event we may not be the
surviving entity. In addition, any increase in the amount of (1) authorized
preferred stock or the creation or issuance of any other series of preferred
stock, or (2) authorized shares of such series or any other series of preferred
stock, in each case ranking on a parity with or junior to the preferred stock of
such series with respect to payment of dividends or the distribution of assets
upon liquidation, dissolution or winding up, shall not be deemed to materially
and adversely affect such rights, preferences, privileges or voting powers.

    The foregoing voting provisions will not apply if, at or prior to the time
when the act with respect to which such vote would otherwise be required will be
effected, we have redeemed or called for redemption all outstanding shares of
such series of preferred stock and, if called for redemption, have deposited
sufficient funds in trust to effect such redemption.

CONVERSION RIGHTS

    The terms and conditions upon which any series of preferred stock is
convertible into common stock will be set forth in the applicable prospectus
supplement relating to the offering of such series of preferred stock. Such
terms will include the number of shares of common stock into which the shares of
preferred stock are convertible, the conversion price, rate or manner of
calculation thereof, the conversion period, provisions as to whether conversion
will be at our option or at the holders' option, the events requiring an
adjustment of the conversion price and provisions affecting conversion in the
event of the redemption.

TRANSFER AGENT

    The transfer agent and registrar for the preferred stock will be set forth
in the applicable prospectus supplement.

                                       24

                          DESCRIPTION OF COMMON STOCK

    The following is a description of the material terms and provisions of our
common stock. It may not contain all the information that is important to you.
Therefore, you should read our charter and bylaws before you purchase any shares
of our common stock.

GENERAL

    Under our charter, we have authority to issue 80,000,000 shares of common
stock, par value $.01 per share, and 3,000,000 shares of Class B common stock,
par value $.01 per share. Under Delaware law, stockholders generally are not
responsible for our debts or obligations. As of December 3, 2001, we had
22,201,453 shares of common stock, and no shares of Class B common stock,
respectively, issued and outstanding. Our common stock is listed on the NYSE
under the symbol "AMG."

DIVIDENDS

    Subject to the preferential rights of any other class or series of stock,
holders of shares of our common stock and Class B common stock will be entitled
to receive dividends out of assets that we may legally use to pay dividends, if
and when they are authorized and declared by our board of directors, with each
share of common stock and each share of Class B common stock sharing equally in
such dividends with each share of Class B common stock being equal to the number
of shares of common stock into which it would then be convertible. If dividends
are declared which are payable in shares of common stock or shares of Class B
common stock, dividends shall be declared which are payable at the same rate in
both classes of stock and the dividends payable in shares of common stock shall
be payable to the holders of shares of common stock, and the dividends payable
in shares of Class B common stock shall be payable to the holders of shares of
Class B common stock.

VOTING RIGHTS

    Except as otherwise required by law and except as provided by the terms of
any other class or series of stock, holders of common stock have the exclusive
power to vote on all matters presented to our stockholders, including the
election of directors. Holders of common stock are entitled to one vote per
share. There is no cumulative voting in the election of our directors, which
means that, subject to any rights to elect directors that are granted to the
holders of any class or series of preferred stock, a plurality of the votes cast
at a meeting of stockholders at which a quorum is present is sufficient to elect
a director.

    To the extent the holders of Class B common stock are entitled to vote under
our charter or applicable law, such holders shall vote together as a single
class with the holders of common stock, except as required by law.

LIQUIDATION/DISSOLUTION RIGHTS

    Subject to the preferential rights of any other class or series of stock,
holders of shares of our common stock and Class B common stock share in the same
proportion as our other stockholders in the assets that we may legally use to
pay distributions in the event we are liquidated, dissolved or our affairs are
wound up after we pay or make adequate provision for all of our known debts and
liabilities with each share of Class B common stock being equal to the number of
shares of common stock into which it would then be convertible.

OTHER RIGHTS

    Subject to the preferential rights of any other class or series of stock,
all shares of our common stock have equal dividend, distribution, liquidation
and other rights, and have no preference, appraisal

                                       25

or exchange rights. Furthermore, holders of shares of our common stock have no
conversion, sinking fund or redemption rights, or preemptive rights to subscribe
for any of our securities, other than the limited conversion rights afforded to
the holders of our Class B common stock which are described below.

    Under Delaware law, a corporation generally cannot dissolve, amend its
charter, merge, sell all or substantially all of its assets, engage in a share
exchange or engage in similar transactions outside the ordinary course of
business unless approved by the affirmative vote of stockholders holding a
majority of the shares entitled to vote on the matter, unless a different
percentage is set forth in the corporation's charter, which percentage shall not
in any event be less than a majority of all of the shares entitled to vote on
such matter. Our charter provides that whenever any vote of the holders of
voting stock is required to amend or repeal any provision of the charter, then
in addition to any other vote of the holders of voting stock that is required by
the charter or bylaw, the affirmative vote of the holders of a majority of our
outstanding shares of stock entitled to vote on such amendment or repeal, voting
together as a single class, is required. However, with respect to the amendment
or repeal of any of the provisions of our charter relating to stockholder action
without an annual or special meeting, the election, term or removal of
directors, vacancies on the board of directors, and the limitation of liability
of directors and officers, the affirmative vote of the holders of at least
eighty percent (80%) of the outstanding shares entitled to vote on such
amendment or repeal, voting together as a single class, shall be required.

RIGHTS OF CLASS B COMMON STOCK

    The holders of our Class B common stock generally have the same rights and
privileges as holders of our common stock, except that holders of Class B common
stock do not have any voting rights other than those which may be provided by
applicable law. Each share of Class B common stock is convertible, at the option
of the holder, into one share of common stock if such share of Class B common
stock is to be distributed, disposed of or sold by the holder in connection with
any sale; provided, that such conversion is not inconsistent with any
regulation, rule or other requirement of any governmental authority applicable
to the holder.

TRANSFER AGENT

    The transfer agent and registrar for the common stock is Mellon Investor
Services.

                  DESCRIPTION OF THE STOCK PURCHASE CONTRACTS
                          AND THE STOCK PURCHASE UNITS

    We may issue stock purchase contracts representing contracts obligating
holders to purchase from us, and us to sell to the holders, a specified number
of shares of our common stock (or a range of numbers of shares pursuant to a
predetermined formula) at a future date or dates. The price per share of common
stock and the number of shares of common stock may be fixed at the time the
stock purchase contracts are issued or may be determined by reference to a
specific formula set forth in the stock purchase contracts.

    The stock purchase contracts may be issued separately or as a part of units,
often known as stock purchase units, consisting of a stock purchase contract and
either:

    - our debt securities; or

    - debt obligations of third parties, including U.S. Treasury securities;

securing the holders' obligations to purchase the common stock under the stock
purchase contracts.

                                       26

    The stock purchase contracts may require us to make periodic payments to the
holders of the stock purchase units or vice versa, and such payments may be
unsecured or prefunded on some basis. The stock purchase contracts may require
holders to secure their obligations in a specified manner and in certain
circumstances we may deliver newly issued prepaid stock purchase contracts,
often known as prepaid securities, upon release to a holder of any collateral
securing such holder's obligations under the original stock purchase contract.

    The applicable prospectus supplement will describe the terms of any stock
purchase contracts or stock purchase units, and, if applicable, prepaid
securities. The description in the applicable prospectus supplement will not
contain all of the information that you may find useful. For more information,
you should review the stock purchase contracts, the collateral arrangements and
depositary arrangements, if applicable, the prepaid securities and the document
contracts or stock purchase units and, if applicable, the prepaid securities and
the document pursuant to which the prepaid securities will be issued. These
documents will be filed with the SEC promptly after the offering of the stock
purchase contracts or stock purchase units. Material United States federal
income tax consideration applicable to the stock purchase contracts and the
stock purchase units will also be discussed in the applicable prospectus
supplement.

                  HOW WE PLAN TO OFFER AND SELL THE SECURITIES

    We may sell the securities in any one or more of the following ways:

    - directly to investors;

    - to investors through agents;

    - to dealers;

    - through underwriting syndicates led by one or more managing underwriters;
      and

    - through one or more underwriters acting alone.

    Any underwritten offering may be on a best efforts or a firm commitment
basis. We may also make direct sales through subscription rights distributed to
our stockholders on a pro rata basis, which may or may not be transferable. In
any distribution of subscription rights to stockholders, if all of the
underlying securities are not subscribed for, we may then sell the unsubscribed
securities directly to third parties or may engage the services of one or more
underwriters, dealers or agents, including standby underwriters, to sell the
unsubscribed securities to third parties.

    The distribution of the securities may be effected from time to time in one
or more transactions:

    - at a fixed price or prices, which may be changed;

    - at market prices prevailing at the time of sale;

    - at prices related to such prevailing market prices; or

    - at negotiated prices.

Any of the prices may represent a discount from the prevailing market prices.

    In the sale of the securities, underwriters or agents may receive
compensation from us or from purchasers of the securities, for whom they may act
as agents, in the form of discounts, concessions or commissions. Underwriters
may sell the securities to or through dealers, and such dealers may receive
compensation in the form of discounts, concessions or commissions from the
underwriters and/or commissions from the purchasers for whom they may act as
agents. Underwriters, dealers and agents that participate in the distribution of
the securities may be deemed to be underwriters under the Securities Act of
1933, and any discounts or commissions they receive from us and any profit on
the

                                       27

resale of securities they realize may be deemed to be underwriting discounts and
commissions under the Securities Act of 1933. The applicable prospectus
supplement will, where applicable:

    - identify any such underwriter or agent;

    - describe any compensation in the form of discounts, concessions,
      commissions or otherwise received from us by each such underwriter or
      agent and in the aggregate to all underwriters and agents;

    - identify the amounts underwritten; and

    - identify the nature of the underwriter's obligation to take the
      securities.

    Unless otherwise specified in the related prospectus supplement, each series
of securities will be a new issue with no established trading market, other than
the common stock which is listed on the NYSE. Any common stock sold pursuant to
a prospectus supplement will be listed on the NYSE, subject to official notice
of issuance. We may elect to list any series of debt securities or preferred
stock, respectively, on an exchange, but we are not obligated to do so. It is
possible that one or more underwriters may make a market in a series of
securities, but such underwriters will not be obligated to do so and may
discontinue any market making at any time without notice. Therefore, no
assurance can be given as to the liquidity of, or the trading market for, any
series of debt securities or preferred stock.

    Until the distribution of the securities is completed, rules of the SEC may
limit the ability of any underwriters and selling group members to bid for and
purchase the securities. As an exception to these rules, underwriters are
permitted to engage in some transactions that stabilize the price of the
securities. Such transactions consist of bids or purchases for the purpose of
pegging, fixing or maintaining the price of the securities.

    If any underwriters create a short position in the securities in an offering
in which they sell more securities than are set forth on the cover page of the
applicable prospectus supplement, the underwriters may reduce that short
position by purchasing the securities in the open market.

    The lead underwriters may also impose a penalty bid on other underwriters
and selling group members participating in an offering. This means that if the
lead underwriters purchase securities in the open market to reduce the
underwriters' short position or to stabilize the price of the securities, they
may reclaim the amount of any selling concession from the underwriters and
selling group members who sold those securities as part of the offering.

    In general, purchases of a security for the purpose of stabilization or to
reduce a short position could cause the price of the security to be higher than
it might be in the absence of such purchases. The imposition of a penalty bid
might also have an effect on the price of a security to the extent that it were
to discourage resales of the security before the distribution is completed.

    We do not make any representation or prediction as to the direction or
magnitude of any effect that the transactions described above might have on the
price of the securities. In addition, we do not make any representation that
underwriters will engage in such transactions or that such transactions, once
commenced, will not be discontinued without notice.

    Under agreements into which we may enter, underwriters, dealers and agents
who participate in the distribution of the securities may be entitled to
indemnification by us against some liabilities, including liabilities under the
Securities Act.

    Underwriters, dealers and agents may engage in transactions with us, perform
services for us or be our tenants in the ordinary course of business.

                                       28

    If indicated in the applicable prospectus supplement, we will authorize
underwriters or other persons acting as our agents to solicit offers by
particular institutions to purchase securities from us at the public offering
price set forth in such prospectus supplement pursuant to delayed delivery
contracts providing for payment and delivery on the date or dates stated in such
prospectus supplement. Each delayed delivery contract will be for an amount no
less than, and the aggregate principal amounts of securities sold under delayed
delivery contracts shall be not less nor more than, the respective amounts
stated in the applicable prospectus supplement. Institutions with which such
contracts, when authorized, may be made include commercial and savings banks,
insurance companies, pension funds, investment companies, educational and
charitable institutions and others, but will in all cases be subject to our
approval. The obligations of any purchaser under any such contract will be
subject to the conditions that (a) the purchase of the securities shall not at
the time of delivery be prohibited under the laws of any jurisdiction in the
United States to which the purchaser is subject, and (b) if the securities are
being sold to underwriters, we shall have sold to the underwriters the total
principal amount of the securities less the principal amount thereof covered by
the contracts. The underwriters and such other agents will not have any
responsibility in respect of the validity or performance of such contracts.

    To comply with applicable state securities laws, the securities offered by
this prospectus will be sold, if necessary, in such jurisdictions only through
registered or licensed brokers or dealers. In addition, securities may not be
sold in some states unless they have been registered or qualified for sale in
the applicable state or an exemption from the registration or qualification
requirement is available and is complied with.

                                    EXPERTS

    The consolidated financial statements incorporated in this prospectus by
reference to the Annual Report on Form 10-K, for the year ended December 31,
2000, have been so incorporated in reliance upon the reports of
PricewaterhouseCoopers LLP, independent accountants, given on the authority of
said firm as experts in auditing and accounting.

                                 LEGAL OPINIONS

    The validity of the securities we are offering will be passed upon for us by
Goodwin Procter LLP, Boston, Massachusetts.

                                       29

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

    You should only rely on the information contained in this prospectus, any
prospectus supplement or any document incorporated by reference. We have not
authorized anyone else to provide you with different or additional information.
We are not making an offer of these securities in any state where the offer is
not permitted. You should not assume that the information in this prospectus or
any prospectus supplement is accurate as of any date other than the date on the
front of those documents.

                            ------------------------

                               TABLE OF CONTENTS



                                          PAGE
                                        --------
                                     
About This Prospectus.................      1

Where You Can Find More Information...      1

Forward-Looking Statements............      2

About Affiliated Managers Group,
  Inc.................................      3

Ratios of Earnings to Fixed Charges...      3

How We Intend to Use the Proceeds.....      3

Description of Debt Securities........      4

Description of Preferred Stock........     19

Description of Common Stock...........     25

Description of Stock Purchase
  Contracts and Stock Purchase
  Units...............................     26

How We Plan to Sell the Securities....     27

Experts...............................     29

Legal Matters.........................     29


                                  $750,000,000


                      
                            AFFILIATED
                             MANAGERS
[LOGO]                      GROUP, INC.


                                DEBT SECURITIES
                                PREFERRED STOCK
                                  COMMON STOCK
                            STOCK PURCHASE CONTRACTS
                            AND STOCK PURCHASE UNITS

                             ---------------------

                                   PROSPECTUS

                             ---------------------

                                DECEMBER 5, 2001

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

                PART II. INFORMATION NOT REQUIRED IN PROSPECTUS

ITEM 14. OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION.

    The expenses in connection with the issuance and distribution of the
securities being registered will be borne by Affiliated Managers Group, Inc. and
are set forth in the following table (all amounts except the registration fee
are estimated):


                                                           
Registration fee............................................  $179,250
Legal fees and expenses.....................................   300,000
Blue Sky expenses...........................................    20,000
Accounting fees and expenses................................   150,000
Printing fees and expenses..................................    50,000
Miscellaneous...............................................   200,750
                                                              --------
    TOTAL...................................................  $900,000
                                                              ========


ITEM 15. INDEMNIFICATION OF DIRECTORS AND OFFICERS.

    In accordance with the General Corporation Law of the State of Delaware,
Article VII of the Amended and Restated Certificate of Incorporation of
Affiliated Managers Group (the "Certificate") provides that no director of ours
shall be personally liable to us or our stockholders for monetary damages for
breach of fiduciary duty as a director, except for liability (i) for any breach
of the director's duty of loyalty to us or our stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) in respect of certain unlawful dividend payments or
stock redemptions or repurchases, or (iv) for any transaction from which the
director derived an improper personal benefit. In addition, the Certificate
provides that if the General Corporation Law of the State of Delaware is amended
to authorize the further elimination or limitation of the liability of
directors, then the liability of a director of the Corporation shall be
eliminated or limited to the fullest extent permitted by the General Corporation
Law of the State of Delaware, as so amended.

    Article V of our Amended and Restated By-laws provides for indemnification,
to the fullest extent authorized by the General Corporation Law of the State of
Delaware (as the same exists or may hereafter be amended; provided that no such
amendment shall reduce the level of indemnity provided prior to such amendment),
by us of our directors, officers and certain non-officer employees under certain
circumstances against expenses (including, among other things, attorneys' fees,
judgments, fines, taxes, penalties and amounts reasonably paid in settlement)
incurred in connection with the defense or settlement of any threatened, pending
or completed legal proceeding (or any claim, issue or matter therein) in which
any such person is involved by reason of the fact that such person is or was a
director, officer or employee of our company if such person acted in good faith
and in a manner he or she has reasonably believed to be in or not opposed to our
best interests, and, with respect to criminal actions or proceedings, if such
person had no reasonable cause to believe his or her conduct was unlawful.

    The Amended and Restated Stockholders' Agreement, filed as Exhibit 10.1 to
our registration statement on Form S-1 (File No. 333-34679) filed on August 29,
1997, as amended (the "Form S-1"), provides for indemnification by us of certain
stockholders and the controlling persons of such stockholders (several of whom
are our officers and directors) against certain liabilities arising under the
securities laws in connection with sales of our common stock by such
stockholders pursuant to the registration rights granted to them under the
Amended and Restated Stockholders' Agreement.

    We also carry standard directors' and officers' liability insurance covering
our directors and officers.

                                      II-1

ITEM 16. EXHIBITS.



EXHIBIT NO.             DESCRIPTION
-----------             -----------
                     
         4.1            Form of Indenture for Senior Debt Securities.
         4.2            Form of Senior Debt Security (included in Exhibit 4.1
                        hereto).
         4.3            Form of Indenture for Subordinated Debt Securities.
         4.4            Form of Subordinated Debt Security (included in Exhibit 4.3
                        hereto).
         5.1            Opinion of Goodwin Procter LLP as to the legality of the
                        Securities being registered.
        12.1            Calculation of Ratios of Earnings to Fixed Charges.
        23.1            Consent of PricewaterhouseCoopers LLP, Independent
                        Accountants.
        23.2            Consent of Goodwin Procter LLP (included in Exhibit 5.1
                        hereto).
        24.1            Powers of Attorney (included in Part II of this registration
                        statement).
        25.1*           Statement of Eligibility of Trustee on Form T-1.


* To be filed by amendment or as an exhibit to a current report on Form 8-K.

ITEM 17. UNDERTAKINGS.

    (a) The undersigned registrant hereby undertakes:

        (1) To file, during any period in which offers or sales are being made,
    a post-effective amendment to this registration statement:

           (i) To include any prospectus required by Section 10(a)(3) of the
       Securities Act;

           (ii) To reflect in the prospectus any facts or events arising after
       the effective date of the registration statement (or the most recent
       post-effective amendment thereof) which, individually or in the
       aggregate, represent a fundamental change in the information set forth in
       the registration statement. Notwithstanding the foregoing, any increase
       or decrease in volume of securities offered (if the total dollar value of
       securities offered would not exceed that which was registered) and any
       deviation from the low or high end of the estimated offering range may be
       reflected in the form of prospectus filed with the Commission pursuant to
       Rule 424(b) if, in the aggregate, the changes in volume and price
       represent no more than a 20% change in the maximum aggregate offering
       price set forth in the "Calculation of Registration Fee" table in the
       effective registration statement; and

           (iii) To include any material information with respect to the plan of
       distribution not previously disclosed in the registration statement or
       any material change to such information in the registration statement;

    PROVIDED, HOWEVER, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if
    the information required to be included in a post-effective amendment by
    those paragraphs is contained in periodic reports filed by the undersigned
    registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that
    are incorporated by reference in the registration statement;

        (2) That, for the purpose of determining any liability under the
    Securities Act, each such post-effective amendment shall be deemed to be a
    new registration statement relating to the securities offered therein, and
    the offering of such securities at that time shall be deemed to be the
    initial BONA FIDE offering thereof; and

        (3) To remove from registration by means of a post-effective amendment
    any of the securities being registered which remain unsold at the
    termination of the offering.

    (b) The registrant hereby undertakes that, for purposes of determining any
       liability under the Securities Act, each filing of the registrant's
       annual report pursuant to Section 13(a) or 15(d)

                                      II-2

       of the Exchange Act (and, where applicable, each filing of an employee
       benefit plan's annual report pursuant to Section 15(d) of the Exchange
       Act) that is incorporated by reference in the registration statement
       shall be deemed to be a new registration statement relating to the
       securities offered therein, and the offering of such securities at that
       time shall be deemed to be the initial BONA FIDE offering thereof.

    (c) Insofar as indemnification for liabilities arising under the Securities
       Act may be permitted to directors, officers and controlling persons of
       the registrant pursuant to the foregoing provisions, or otherwise, the
       registrant has been advised that in the opinion of the Commission such
       indemnification is against public policy as expressed in the Act and is,
       therefore, unenforceable. In the event that a claim for indemnification
       against such liabilities (other than the payment by the registrant of
       expenses incurred or paid by a director, officer or controlling person of
       the registrant in the successful defense of any action, suit or
       proceeding) is asserted by such director, officer or controlling person
       in connection with the securities being registered, the registrant will,
       unless in the opinion of its counsel the matter has been settled by
       controlling precedent, submit to a court of appropriate jurisdiction the
       question whether such indemnification by it is against public policy as
       expressed in the Act and will be governed by the final adjudication of
       such issue.

    (d) The registrant hereby undertakes to file an application for the purpose
       of determining the eligibility of the trustee to act under subsection
       (a) of Section 310 of the Trust Indenture Act in accordance with the
       rules and regulations prescribed by the Commission under
       Section 305(b)(2) of the Trust Indenture Act.

                                      II-3

                                   SIGNATURES

    Pursuant to the requirements of the Securities Act, Affiliated Managers
Group, Inc. certifies that it has reasonable grounds to believe that it meets
all of the requirements for filing on Form S-3 and has duly caused this
registration statement (the "Registration Statement") to be signed on its behalf
by the undersigned, thereunto duly authorized, in the City of Boston,
Commonwealth of Massachusetts, on this 4th day of December, 2001.


                                                      
                                                       AFFILIATED MANAGERS GROUP, INC.

                                                       By:             /s/ DARRELL W. CRATE
                                                            -----------------------------------------
                                                                         Darrell W. Crate
                                                            EXECUTIVE VICE PRESIDENT, CHIEF FINANCIAL
                                                                      OFFICER AND TREASURER


    KNOW ALL MEN BY THESE PRESENTS, that we, the undersigned officers and
directors of Affiliated Managers Group, Inc. hereby constitute Darrell W. Crate
our true and lawful attorney with full power to sign for us and in our names in
the capacities indicated below, the Registration Statement filed herewith, a
registration statement on Form S-3, which may be subsequently filed pursuant to
Rule 462(b) of the Securities Act, and which would incorporate by reference this
Registration Statement, and any and all amendments to either of said
registration statements, and generally to do all such things in our names and in
our capacities as officers and directors to enable Affiliated Managers
Group, Inc. to comply with the provisions of the Securities Act and all
requirements of the Commission, hereby ratifying and confirming our signatures
as they may be signed by our said attorney, to either of said registration
statements and any and all amendments thereto.

    Pursuant to the requirements of the Securities Act, this Registration
Statement has been signed by the following persons in the capacities and on the
dates indicated.



                      SIGNATURE                                 CAPACITY                  DATE
                      ---------                                 --------                  ----
                                                                              
                                                       Chairman of the Board of
                 /s/ WILLIAM J. NUTT                   Directors and Chief
     -------------------------------------------       Executive Officer            December 4, 2001
                   William J. Nutt                     (Principal Executive
                                                       Officer)

                                                       Executive Vice President,
                /s/ DARRELL W. CRATE                   Chief Financial Officer and
     -------------------------------------------       Treasurer (Principal         December 4, 2001
                  Darrell W. Crate                     Financial and Accounting
                                                       Officer)

                 /s/ SEAN M. HEALEY
     -------------------------------------------       President, Chief Operating   December 4, 2001
                   Sean M. Healey                      Officer and Director

                /s/ RICHARD E. FLOOR
     -------------------------------------------       Director                     December 4, 2001
                  Richard E. Floor


                                      II-4




                      SIGNATURE                                 CAPACITY                  DATE
                      ---------                                 --------                  ----
                                                                              
               /s/ STEPHEN J. LOCKWOOD
     -------------------------------------------       Director                     December 4, 2001
                 Stephen J. Lockwood

               /s/ HAROLD J. MEYERMAN
     -------------------------------------------       Director                     December 4, 2001
                 Harold J. Meyerman

                /s/ RITA M. RODRIGUEZ
     -------------------------------------------       Director                     December 4, 2001
                  Rita M. Rodriguez

                 /s/ WILLIAM F. WELD
     -------------------------------------------       Director                     December 4, 2001
                   William F. Weld


                                      II-5

                                 EXHIBIT INDEX



EXHIBIT NO.             DESCRIPTION
-----------             -----------
                     
         4.1            Form of Indenture for Senior Debt Securities.
         4.2            Form of Senior Debt Security (included in Exhibit 4.1
                        hereto).
         4.3            Form of Indenture for Subordinated Debt Securities.
         4.4            Form of Subordinated Debt Security (included in Exhibit 4.3
                        hereto).
         5.1            Opinion of Goodwin Procter LLP as to the legality of the
                        Securities being registered.
        12.1            Calculation of Ratios of Earnings to Fixed Charges.
        23.1            Consent of PricewaterhouseCoopers LLP, Independent
                        Accountants.
        23.2            Consent of Goodwin Procter LLP (included in Exhibit 5.1
                        hereto).
        24.1            Powers of Attorney (included in Part II of this registration
                        statement).
        25.1*           Statement of Eligibility of Trustee on Form T-1.


* To be filed by amendment or as an exhibit to a current report on Form 8-K.