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                                                                     EXHIBIT 4.5

                              REMARKETING AGREEMENT

      REMARKETING AGREEMENT, dated as of December 21, 2001 (the "Remarketing
Agreement") by and among Affiliated Managers Group, Inc., a company organized
and existing under the laws of the State of Delaware (the "Company"), First
Union National Bank, a national banking association, not individually but
solely as Purchase Contract Agent and as attorney-in-fact of the holders of
Purchase Contracts (each as defined in the Purchase Contract Agreement (as
defined herein)), and Merrill Lynch & Co., Merrill Lynch, Pierce, Fenner &
Smith Incorporated (the "Merrill Lynch").

                                   WITNESSETH:

      WHEREAS, the Company has issued its FELINE PRIDES (the "FELINE PRIDES")
in an aggregate Stated Amount of $200,000,000 (or $230,000,000 if the
underwriters' overallotment option is exercised in full) under the Purchase
Contract Agreement, dated as of December 21, 2001, by and between the
Purchase Contract Agent and the Company (the "Purchase Contract Agreement");
and

      WHEREAS, the Company will issue concurrently in connection with the
issuance of the FELINE PRIDES 6% Senior Notes of the Company due November 17,
2006 (the "Notes") in an aggregate principal amount of $200,000,000 (or
$230,000,000 if the underwriters' overallotment option is exercised in full);
and

      WHEREAS, the FELINE PRIDES will initially consist of 8,000,000 (or
9,200,000 if the underwriters' overallotment option is exercised in full)
units referred to as "Income PRIDES"; and

      WHEREAS, the Notes forming a part of the Income Prides will be pledged
pursuant to the Pledge Agreement (the "Pledge Agreement"), dated as of
December 21, 2001, by and among the Company, First Union National Bank, as
collateral agent (the "Collateral Agent"), and the Purchase Contract Agent,
to secure an Income PRIDES holder's obligations under the related Purchase
Contract on the Purchase Contract Settlement Date; and

      WHEREAS, the Notes of the Noteholders electing to have their Notes
remarketed and of the Income PRIDES holders will be remarketed by the
Remarketing Agent on the third Business Day immediately preceding August 17,
2004 (the "Initial Remarketing Date"); and

      WHEREAS, in the event of a Failed Initial Remarketing, the Notes of the
Noteholders electing to have their Notes remarketed and of the Income PRIDES
holders who have elected not to settle the Purchase Contracts related to
their Income PRIDES by Cash Settlement and who have not settled their
Purchase Contracts early upon the occurrence of a corporate transaction will
be remarketed by the Remarketing Agent on the third Business Day immediately
preceding the Purchase Contract Settlement Date; and

      WHEREAS, in the event of a Successful Initial Remarketing, the
applicable interest rate on the Notes will be reset on the Initial
Remarketing Date, to the Reset Rate to be determined by

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the Reset Agent as the rate that such Notes should bear in order for the
Applicable Principal Amount of the Notes to have an approximate aggregate
market value of 100.5% of the Treasury Portfolio Purchase Price on the
Initial Remarketing Date, provided that in the determination of such Reset
Rate, the Company shall, if applicable, limit the Reset Rate to the maximum
rate permitted by applicable law; and

      WHEREAS, in the event of a Failed Initial Remarketing, the applicable
interest rate on the Notes that remain outstanding on and after the Purchase
Contract Settlement Date will be reset on the third Business Day immediately
preceding the Purchase Contract Settlement Date, to the Reset Rate to be
determined by the Reset Agent as the rate that such Notes should bear in
order to have an approximate market value of 100.5% of the aggregate
principal amount of the Notes on the third Business Day immediately preceding
the Purchase Contract Settlement Date, provided that in the determination of
such Reset Rate, the Company shall, if applicable, limit the Reset Rate to
the maximum rate permitted by applicable law; and

      WHEREAS, the Company has requested Merrill Lynch to act as the Reset
Agent and as the Remarketing Agent, and as such to perform the services
described herein; and

      WHEREAS, Merrill Lynch is willing to act as Reset Agent and Remarketing
Agent and as such to perform such duties on the terms and conditions
expressly set forth herein;

      NOW, THEREFORE, for and in consideration of the covenants herein made,
and subject to the conditions herein set forth, the parties hereto agree as
follows:

      Section 1.  DEFINITIONS. Capitalized terms used and not defined in this
Agreement shall have the meanings assigned to them in the Purchase Contract
Agreement or, if not therein defined, the Pledge Agreement.

      Section 2.  APPOINTMENT AND OBLIGATIONS OF REMARKETING AGENT.

      (a) The Company hereby appoints Merrill Lynch and Merrill Lynch hereby
accepts such appointment, (i) as the Reset Agent to determine in consultation
with the Company, in the manner provided for herein and in the Indenture (as
in effect on the date of this Remarketing Agreement) with respect to the
Notes, (1) the Reset Rate that, in the opinion of the Reset Agent, will, when
applied to the Notes, enable the Applicable Principal Amount of the Notes to
have an approximate aggregate market value of 100.5% of the Treasury
Portfolio Purchase Price as of the Initial Remarketing Date, and (2) in the
event of a Failed Initial Remarketing, the Reset Rate that, in the opinion of
the Reset Agent, will, when applied to the Notes, enable a Note to have an
approximate market value of 100.5% of its principal amount as of the third
Business Day preceding the Purchase Contract Settlement Date, provided, in
each case, that the Company, by notice to the Reset Agent prior to the tenth
Business Day preceding August 17, 2004, in the case of the Initial
Remarketing (as defined below), or the Purchase Contract Settlement Date, in
the case of the Secondary Remarketing (as defined below), shall, if
applicable, limit the Reset Rate so that it does not exceed the maximum rate
permitted by applicable law) and (ii) as the exclusive Remarketing Agent
(subject to the right of Merrill Lynch to appoint additional remarketing
agents hereunder as described below) to (1) remarket the Notes of the Note
holders electing to have their Notes remarketed and of the Income PRIDES
holders on the Initial

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Remarketing Date, for settlement on August 17, 2004 and (2) in the case of a
Failed Initial Remarketing, remarket the Notes of the Note holders electing
to have their Notes remarketed or of the Income PRIDES holders who have not
early settled the related Purchase Contracts and have failed to notify the
Purchase Contract Agent, on or prior to the fifth Business Day immediately
preceding the Purchase Contract Settlement Date, of their intention to settle
the related Purchase Contracts through Cash Settlement. In connection with
the remarketing contemplated hereby, the Remarketing Agent will enter into a
Remarketing Underwriting Agreement (the "Remarketing Underwriting Agreement")
with the Company and the Purchase Contract Agent, which shall either be (i)
substantially in the form attached hereto as Exhibit A (with such changes as
the Company and the Remarketing Agent may agree upon, it being understood
that changes may be necessary in the representations, warranties, covenants
and other provisions of the Remarketing Underwriting Agreement due to changes
in law or facts and circumstances or in the event that Merrill Lynch is not
the sole remarketing agent, and with such further changes therein as the
Remarketing Agent may reasonably request, or (ii) in such other form as the
Remarketing Agent may reasonably request, subject to the approval of the
Company (such approval not to be unreasonably withheld). Anything herein to
the contrary notwithstanding, Merrill Lynch shall not be obligated to act as
Remarketing Agent or Reset Agent hereunder unless the Remarketing
Underwriting Agreement is in form and substance reasonably satisfactory to
Merrill Lynch. The Company agrees that Merrill Lynch shall have the right, on
15 Business Days notice to the Company, to appoint one or more additional
remarketing agents so long as any such additional remarketing agents shall be
reasonably acceptable to the Company. Upon any such appointment, the parties
shall enter into an appropriate amendment to this Agreement to reflect the
addition of any such remarketing agent.

      (b) Pursuant to the Remarketing Underwriting Agreement, the Remarketing
Agent, either as sole remarketing agent or as representative of a group of
remarketing agents appointed as aforesaid, will agree, subject to the terms
and conditions set forth herein and therein, to use its reasonable efforts to
(i) remarket, on the Initial Remarketing Date (the "Initial Remarketing"),
the Notes that the Trustee (as such term is defined in the Indenture) shall
have notified the Remarketing Agent have been tendered for, or otherwise are
to be included in, the Initial Remarketing, at a price per Note such that the
aggregate price for the Applicable Principal Amount of the Notes is
approximately 100.5% of the Treasury Portfolio Purchase Price and (ii) in the
event of a Failed Initial Remarketing, remarket, on the third Business Day
immediately preceding the Purchase Contract Settlement Date (the "Secondary
Remarketing"), the Notes that the Trustee shall have notified the Remarketing
Agent have been tendered for, or otherwise are to be included in, the
Secondary Remarketing, at a price of approximately 100.5% of the aggregate
principal amount of such Notes. Notwithstanding the preceding sentence, the
Remarketing Agent shall not remarket any Notes for a price less than the
price necessary for the Applicable Principal Amount of the Notes to have an
aggregate price equal to 100% of the Treasury Portfolio Purchase Price (the
"Minimum Initial Remarketing Price"), in the case of the Initial Remarketing,
or the aggregate principal amount of such Notes, in the case of the Secondary
Remarketing. After deducting the fee specified in Section 3 below, the
proceeds of such Initial Remarketing or Secondary Remarketing, as the case
may be, shall be paid to the Collateral Agent in accordance with Section 4.6
or 6.3 of the Pledge Agreement and Section 5.2 of the Purchase Contract
Agreement (each of which Sections are incorporated herein by reference). The
right of each holder of Notes or Income PRIDES to have Notes tendered for the
Initial Remarketing or the Secondary Remarketing, as the case may be, shall
be limited to the

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extent that (i) the Remarketing Agent conducts an Initial Remarketing and, in
the event of a Failed Initial Remarketing, a Secondary Remarketing pursuant
to the terms of this Agreement, (ii) Notes tendered have not been called for
redemption, (iii) the Remarketing Agent is able to find a purchaser or
purchasers for tendered Notes at a price of not less than the Minimum Initial
Remarketing Price, in the case of the Initial Remarketing, and 100% of the
principal amount thereof, in the case of the Secondary Remarketing and (iv)
such purchaser or purchasers deliver the purchase price therefor to the
Remarketing Agent as and when required.

      (c) It is understood and agreed that neither the Remarketing Agent nor
the Reset Agent shall have any obligation whatsoever to purchase any Notes,
whether in the Initial Remarketing, Secondary Remarketing or otherwise, and
shall in no way be obligated to provide funds to make payment upon tender of
Notes for remarketing or to otherwise expend or risk their own funds or incur
or be exposed to financial liability in the performance of their respective
duties under this Agreement or the Remarketing Underwriting Agreement, and,
without limitation of the foregoing, the Remarketing Agent shall not be
deemed an underwriter of the remarketed Notes. The Company shall not be
obligated in any case to provide funds to make payment upon tender of Notes
for remarketing.

      Section 3. FEES. In the event of a Successful Initial Remarketing, the
Remarketing Agent shall retain as a remarketing fee (the "Remarketing Fee")
an amount not exceeding 25 basis points (0.25%) of the Minimum Initial
Remarketing Price from any amount received in connection with such Initial
Remarketing in excess of the Minimum Initial Remarketing Price. In the event
of a Successful Secondary Remarketing, the Remarketing Agent shall retain as
the Remarketing Fee an amount not exceeding 25 basis points (0.25%), of the
principal amount of the remarketed Notes from any amount received in
connection with such Secondary Remarketing in excess of the aggregate
principal amount of such remarketed Notes. In addition, the Reset Agent
shall, in either case, receive from the Company a reasonable and customary
fee (the "Reset Agent Fee"); provided, however, that if the Remarketing Agent
shall also act as the Reset Agent, then the Reset Agent shall not be entitled
to receive any such Reset Agent Fee. Payment of such Reset Agent Fee shall be
made by the Company on the Initial Remarketing Date, in the case of a
Successful Initial Remarketing, or on the third Business Day immediately
preceding the Purchase Contract Settlement Date, in the case of a Successful
Secondary Remarketing, in immediately available funds or, upon the
instructions of the Reset Agent, by certified or official bank check or
checks or by wire transfer.

      Section 4.  REPLACEMENT AND RESIGNATION OF REMARKETING AGENT.

      (a) The Company may in its absolute discretion replace Merrill Lynch as
the Remarketing Agent and as the Reset Agent hereunder by giving notice prior
to 3:00 p.m., New York City time (i) on the eleventh Business Day immediately
prior to August 17, 2004, or (ii) in the event of a Failed Initial
Remarketing, prior to 3:00 p.m., New York City time on the eleventh Business
Day immediately prior to the Purchase Contract Settlement Date, provided, in
either case, that the Company must replace Merrill Lynch both as Remarketing
Agent and as Reset Agent unless Merrill Lynch shall otherwise agree. Any such
replacement shall become effective upon the Company's appointment of a
successor to perform the services that would otherwise be performed hereunder
by the Remarketing Agent and the Reset Agent. Upon providing such

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notice, the Company shall use all reasonable efforts to appoint such a
successor and to enter into a remarketing agreement with such successor as
soon as reasonably practicable.

      (b) Merrill Lynch may resign at any time and be discharged from its
duties and obligations hereunder as the Remarketing Agent and/or as the Reset
Agent by giving notice prior to 3:00 p.m., New York City time (i) on the
eleventh Business Day immediately prior to August 17, 2004, or (ii) in the
event of a Failed Initial Remarketing, on the eleventh Business Day
immediately prior to the Purchase Contract Settlement Date. Any such
resignation shall become effective upon the Company's appointment of a
successor to perform the services that would otherwise be performed hereunder
by the Remarketing Agent and/or the Reset Agent. Upon receiving notice from
the Remarketing Agent and/or the Reset Agent that it wishes to resign
hereunder, the Company shall appoint such a successor and enter into a
remarketing agreement with it as soon as reasonably practicable.

      Section 5. DEALING IN THE SECURITIES. Each of the Remarketing Agent and
the Reset Agent, when acting hereunder or, in the case of the Remarketing
Agent, under the Remarketing Underwriting Agreement, or when acting in its
individual or any other capacity, may, to the extent permitted by law, buy,
sell, hold or deal in any of the Notes, Growth PRIDES, Income PRIDES or any
other securities of the Company. With respect to any Notes, Growth PRIDES,
Income PRIDES or any other securities of the Company owned by it, each of the
Remarketing Agent and the Reset Agent may exercise any vote or join in any
action with like effect as if it did not act in any capacity hereunder. Each
of the Remarketing Agent and the Reset Agent, in its individual capacity,
either as principal or agent, may also engage in or have an interest in any
financial or other transaction with the Company as freely as if it did not
act in any capacity hereunder.

      Section 6.  REGISTRATION STATEMENT AND PROSPECTUS.

      (a) In connection with the Initial Remarketing, if and to the extent
required in the view of counsel (which need not be an opinion) for either the
Remarketing Agent or the Company by applicable law, regulations or
interpretations in effect at the time of such Initial Remarketing, the
Company (i) shall use its reasonable efforts to have a registration statement
relating to the Notes effective under the Securities Act of 1933 prior to the
third Business Day immediately preceding August 17, 2004, (ii) if requested
by the Remarketing Agent shall furnish a current preliminary prospectus and,
if applicable, a current preliminary prospectus supplement to be used by the
Remarketing Agent in the Initial Remarketing not later than seven Business
Days prior to August 17, 2004 (or such earlier date as the Remarketing Agent
may reasonably request) and in such quantities as the Remarketing Agent may
reasonably request, and (iii) shall furnish a current final prospectus and,
if applicable, a final prospectus supplement to be used by the Remarketing
Agent in the Initial Remarketing not later than the third Business Day
immediately preceding August 17, 2004 in such quantities as the Remarketing
Agent may reasonably request, and shall pay all expenses relating thereto.

      (b) In the event of a Failed Initial Remarketing and in connection with
the Secondary Remarketing, if and to the extent required in the view of
counsel (which need not be an opinion) for either the Remarketing Agent or
the Company by applicable law, regulations or interpretations in effect at
the time of such Secondary Remarketing, the Company (i) shall use its

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reasonable efforts to have a registration statement relating to the Notes
effective under the Securities Act of 1933 prior to the third Business Day
immediately preceding the Purchase Contract Settlement Date, (ii) if
requested by the Remarketing Agent, shall furnish a current preliminary
prospectus and, if applicable, a current preliminary prospectus supplement to
be used by the Remarketing Agent in the Secondary Remarketing not later than
seven Business Days prior to the Purchase Contract Settlement Date (or such
earlier date as the Remarketing Agent may reasonably request) and in such
quantities as the Remarketing Agent may reasonably request, and (iii) shall
furnish a current final prospectus and, if applicable, a final prospectus
supplement to be used by the Remarketing Agent in the Secondary Remarketing
not later than the third Business Day immediately preceding the Purchase
Contract Settlement Date in such quantities as the Remarketing Agent may
reasonably request, and shall pay all expenses relating thereto.

      (c) If in connection with the Initial Remarketing or, in the event of a
Failed Initial Remarketing, the Secondary Remarketing it shall not be
possible, in the view of counsel (which need not be an opinion) for either
the Remarketing Agent or the Company, under applicable law, regulations or
interpretations in effect at the time of such Initial Remarketing or such
Secondary Remarketing to register the offer and sale by the Company of the
Notes under the Securities Act of 1933 as otherwise contemplated by this
Section 6, the Company (i) shall use its reasonable efforts to take, or cause
to be taken, all action and to do, or cause to be done, all things necessary,
proper and advisable to permit and effectuate the offer and sale of the Notes
in connection with the Initial Remarketing or the Secondary Remarketing, as
the case may be, without registration under the Securities Act of 1933
pursuant to an exemption therefrom, if available, including the exemption
afforded by Rule 144A under the rules and regulations promulgated under the
Securities Act of 1933 by the Securities and Exchange Commission, (ii) if
requested by the Remarketing Agent shall furnish a current preliminary
remarketing memorandum to be used by the Remarketing Agent in the Initial
Remarketing or the Secondary Remarketing, as the case may be, not later than
seven Business Days prior to August 17, 2004, in the case of the Initial
Remarketing, or the Purchase Contract Settlement Date, in the case of the
Secondary Remarketing (or in either case such earlier date as the Remarketing
Agent may reasonably request) and in such quantities as the Remarketing Agent
may reasonably request and (iii) shall furnish a current final remarketing
memorandum to be used by the Remarketing Agent in the Initial Remarketing or
the Secondary Remarketing, as the case may be, not later than the third
Business Day immediately preceding August 17, 2004, in the case of the
Initial Remarketing, or the Purchase Contract Settlement Date, in the case of
the Secondary Remarketing, in such quantities as the Remarketing Agent may
reasonably request, and shall pay all expenses relating thereto.

      (d) The Company shall also take all such actions as may (upon advice of
counsel to the Company or the Remarketing Agent) be necessary or desirable
under state securities or blue sky laws in connection with the Initial
Remarketing and the Secondary Remarketing.

      Section 7.  CONDITIONS TO THE REMARKETING AGENT'S OBLIGATIONS.

      (a) The obligations of the Remarketing Agent and the Reset Agent under
this Agreement and, in the case of the Remarketing Agent, the Remarketing
Underwriting Agreement shall be subject to the terms and conditions of this
Agreement and the Remarketing Underwriting

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Agreement, including, without limitation, the following conditions: (i) the
Notes tendered for, or otherwise to be included in the Initial Remarketing or
Secondary Remarketing, as the case may be, have not been called for
redemption, (ii) the Remarketing Agent is able to find a purchaser or
purchasers for tendered Notes (1) in the case of the Initial Remarketing, at
a price not less than Minimum Initial Remarketing Price, and (2) in the case
of the Secondary Remarketing, at a price not less than 100% of the principal
amount thereof, (iii) the Purchase Contract Agent, the Collateral Agent, the
Custodial Agent, the Company and the Trustee shall have performed their
respective obligations in connection with the Initial Remarketing and, in the
event of a Failed Initial Remarketing, in connection with the Secondary
Remarketing, in each case pursuant to the Purchase Contract Agreement, the
Pledge Agreement, the Indenture, this Agreement and the Remarketing
Underwriting Agreement (including, without limitation, giving the Remarketing
Agent notice of the Treasury Portfolio Purchase Price no later than 10:00
a.m., New York City time, on the fourth Business Day prior to August 17,
2004, in the case of the Initial Remarketing, and giving the Remarketing
Agent notice of the aggregate principal amount, as the case may be, of Notes
to be remarketed, no later than 10:00 a.m., New York City time, on the fourth
Business Day prior to the Purchase Contract Settlement Date, in the case of
the Secondary Remarketing, and, in each case, concurrently delivering the
Notes to be remarketed to the Remarketing Agent), (iv) no Event of Default
(as defined in the Indenture) shall have occurred and be continuing, (v) the
accuracy of the representations and warranties of the Company included and
incorporated by reference in this Agreement and the Remarketing Underwriting
Agreement or in certificates of any officer of the Company or any of its
subsidiaries delivered pursuant to the provisions included or incorporated by
reference in this Agreement or the Remarketing Underwriting Agreement, (vi)
the performance by the Company of its covenants and other obligations
included and incorporated by reference in this Agreement and the Remarketing
Underwriting Agreement, and (vii) the satisfaction of the other conditions
set forth and incorporated by reference in this Agreement and the Remarketing
Underwriting Agreement.

      (b) If at any time during the term of this Agreement, any Event of
Default or event that with the passage of time or the giving of notice or
both would become an Event of Default has occurred and is continuing under
the Indenture, then the obligations and duties of the Remarketing Agent and
the Reset Agent under this Agreement and the Remarketing Underwriting
Agreement shall be suspended until such default or event has been cured. The
Company will promptly give the Remarketing Agent notice of all such defaults
and events of which the Company is aware.

      Section 8. TERMINATION OF REMARKETING AGREEMENT. This Agreement shall
terminate as to the Remarketing Agent and/or the Reset Agent on the effective
date of its replacement pursuant to Section 4(a) hereof or pursuant to
Section 4(b) hereof.

      Section 9. REMARKETING AGENT'S PERFORMANCE; DUTY OF CARE. The duties
and obligations of the Remarketing Agent hereunder shall be determined solely
by the express provisions of this Agreement and the Remarketing Underwriting
Agreement.

      Section 10.  GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD
TO CONFLICTS OF LAWS PRINCIPLES THEREOF.

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      Section 11. TERM OF AGREEMENT. Unless otherwise terminated in
accordance with the provisions hereof and except as otherwise provided
herein, this Agreement shall remain in full force and effect from the date
hereof until the first day thereafter on which no Notes are outstanding, or,
if earlier, the Business Day immediately following August 17, 2004, in the
case of a Successful Initial Remarketing, or the Business Day immediately
following the Purchase Contract Settlement Date, in the case of a Successful
Secondary Remarketing.

      Section 12. SUCCESSORS AND ASSIGNS. The rights and obligations of the
Company hereunder may not be assigned or delegated to any other person
without the prior written consent of Merrill Lynch as the Remarketing Agent
and/or as the Reset Agent. The rights and obligations of Merrill Lynch as the
Remarketing Agent and/or as the Reset Agent hereunder may not be assigned or
delegated to any other person without the prior written consent of the
Company. This Agreement shall inure to the benefit of and be binding upon the
Company and Merrill Lynch as the Remarketing Agent and/or as the Reset Agent
and their respective successors and assigns. The terms "successors" and
"assigns" shall not include any purchaser of Securities merely because of
such purchase.

      Section 13. HEADINGS. Section headings have been inserted in this
Agreement and the Remarketing Underwriting Agreement as a matter of
convenience of reference only, and it is agreed that such section headings
are not a part of this Agreement or the Remarketing Underwriting Agreement
and will not be used in the interpretation of any provision of this Agreement
or the Remarketing Underwriting Agreement.

      Section 14. SEVERABILITY. If any provision of this Agreement or the
Remarketing Underwriting Agreement shall be held or deemed to be or shall, in
fact, be invalid, inoperative or unenforceable as applied in any particular
case in any or all jurisdictions because it conflicts with any provisions of
any constitution, statute, rule or public policy or for any other reason,
such circumstances shall not have the effect of rendering the provision in
question invalid, inoperative or unenforceable in any other case,
circumstances or jurisdiction, or of rendering any other provision or
provisions of this Agreement or the Remarketing Underwriting Agreement, as
the case may be, invalid, inoperative or unenforceable to any extent
whatsoever.

      Section 15.  COUNTERPARTS. This Agreement or the Remarketing
Underwriting Agreement may be executed in counterparts, each of which shall
be regarded as an original and all of which shall constitute one and the same
document.

      Section 16.  AMENDMENTS. This Agreement and the Remarketing
Underwriting Agreement may be amended by any instrument in writing signed by
the parties hereto.

      Section 17. NOTICES. Unless otherwise specified, any notices, requests,
consents or other communications given or made hereunder or pursuant hereto
shall be made in writing or transmitted by any standard form of
telecommunication, including telephone, telegraph or telecopy, and confirmed
in writing. All written notices and confirmations of notices by
telecommunication shall be deemed to have been validly given or made when
delivered or mailed, registered or certified mail, return receipt requested
and postage prepaid. All such notices, requests, consents or other
communications shall be addressed as follows: if to the Company, Affiliated
Managers Group, Inc., 600 Hale Street, Prides Crossing, MA 01965,

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Attention: Darrell W. Crate, with a copy to Goodwin Procter LLP, Exchange
Place, Boston, MA 02109-2881, Attention: Martin Carmichael; if to the
Remarketing Agent or Reset Agent (if Merrill Lynch, Pierce, Fenner & Smith
Incorporated is the Remarketing Agent or the Reset Agent), to Merrill Lynch,
Pierce, Fenner & Smith Incorporated, 4 World Financial Center, North Tower,
New York, New York 10080, Attention: Investment Banking, with a copy to
Sidley Austin Brown & Wood LLP, 875 Third Avenue, New York, NY 10022,
Attention: L. Markus Wiltshire; and if to the Purchase Contract Agent, to
First Union National Bank, 12 East 49th Street, New York, New York 10017,
Attention: Corporate Trust - NY 4040, or to such other address as any of the
above shall specify to the other in writing.

      Section 18. CONSENT TO JURISDICTION; MISCELLANEOUS. Each of the parties
hereto hereby expressly and irrevocably submits to the non-exclusive
jurisdiction of any competent court in the place of its domicile and any
United States Federal or New York State court sitting in the Borough of
Manhattan in The City of New York in any action, suit or proceeding arising
out of or relating to this Agreement or the transactions contemplated hereby
to the extent that such court has subject matter jurisdiction over the
controversy, and expressly and irrevocably waives, to the extent permitted
under applicable law, any immunity from the jurisdiction thereof and any
claim or defense in such action, suit or proceeding based on a claim of
improper venue, FORUM NON CONVENIENS or any similar basis to which it might
otherwise be entitled in any such action, suit or proceeding.

      Section 19. WAIVER OF IMMUNITIES. To the extent that the Company or any
of its properties, assets or revenues may have or may hereafter become
entitled to, or have attributed to them, any right of immunity, on the
grounds of sovereignty, from any legal action, suit or proceeding, from
set-off or counterclaim, from the jurisdiction of any court, from service of
process, from attachment upon or prior to judgment, or from attachment in aid
of execution of judgment, or from execution of judgment, other legal process
or proceeding for the giving of any relief or for the enforcement of any
judgment, in any jurisdiction in which proceedings may at any time be
commenced, with respect to their obligations, liabilities or any other matter
under or arising out of or in connection with this Agreement or any
additional agreement, the Company hereby irrevocably and unconditionally, to
the extent permitted by applicable law, waives and agrees not to plead or
claim any such immunity and consents to such relief and enforcement.

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      IN WITNESS WHEREOF, each of the Company, the Purchase Contract Agent
and the Remarketing Agent has caused this Agreement to be executed in its
name and on its behalf by one of its duly authorized officers as of the date
first above written.

                                    AFFILIATED MANAGERS GROUP, INC.

                                    By:  /s/ Darrell W. Crate
                                       ---------------------------------------
                                         Name:   Darrell W. Crate
                                         Title:  Chief Financial Officer

CONFIRMED AND ACCEPTED:

MERRILL LYNCH & CO.
MERRILL LYNCH, PIERCE, FENNER & SMITH
            INCORPORATED

By: /s/ Jay C. Horgen
   -------------------------------
    Name:   Jay C. Horgen
    Title:  Vice President

FIRST UNION NATIONAL BANK
not individually but solely as Purchase Contract
Agent and as attorney-in-fact for the holders of
the Purchase Contracts

By: /s/ David Massa
   -------------------------------
    Name:   David Massa
    Title:  Vice President

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                                                                    Exhibit A to
                                                           Remarketing Agreement

                  FORM OF REMARKETING UNDERWRTING AGREEMENT

      Merrill Lynch & Co., Merrill Lynch, Pierce, Fenner & Smith Incorporated
(the "Remarketing Underwriter") hereby agrees to purchase the Notes (the
"Securities"), that have been tendered by the holders of the Notes or the
Income PRIDES for sale on November 17, 2004.

      1. DEFINITIONS. Capitalized terms used and not defined in this
Agreement shall have the meanings assigned to them in the purchase contract
agreement (the "Purchase Contract Agreement"), the pledge agreement (the
"Pledge Agreement"), the underwriting agreement (the "Underwriting
Agreement"), each as identified in Schedule I hereto.

      2. REGISTRATION STATEMENT AND PROSPECTUS. If required (in the opinion
of counsel to either the Remarketing Underwriter or the Company) by
applicable law, the Company has filed with the Securities and Exchange
Commission, and there has become effective, a registration statement on Form
S-3 (No. 333-74558), including a prospectus, relating to the Securities. Such
registration statement, as amended to the date of this Agreement, is
hereinafter referred to as the "Registration Statement," the prospectus
included in the Registration Statement is hereinafter referred to as the
"Basic Prospectus" and the Basic Prospectus, as amended or supplemented to
the date of this Agreement to relate to the Securities and to the remarketing
of the Securities, is hereinafter referred to as the "Final Prospectus"
(including in each case all documents incorporated by reference).

      3. PROVISIONS INCORPORATED BY REFERENCE. (a) Subject to Section 3(b),
the provisions of the Underwriting Agreement shall be incorporated, as
applicable, into this Agreement and made applicable to the obligations of the
Remarketing Underwriter, except as explicitly amended hereby (with such
changes as the Company, the Purchase Contract Agent and the Remarketing Agent
may agree upon, it being understood that changes may be necessary in the
representations, warranties, covenants and other provisions hereof due to
changes in law or facts and circumstances).

      (b) With respect to the provisions of the Underwriting Agreement
incorporated herein, for the purposes hereof, (i) all references therein to
the "Underwriter" or "Underwriters" shall be deemed to refer to the
Remarketing Underwriter; (ii) all references therein to the "Securities"
which are the subject thereof shall be deemed to refer to the Securities as
defined herein; (iii) all references therein to the "Closing Date" shall be
deemed to refer to the Remarketing Closing Date specified in Schedule I
hereto (the "Remarketing Closing Date"); (iv) all references therein to the
"Registration Statement" and the "Prospectus" shall be deemed to refer to the
Registration Statement and the Final Prospectus, respectively, as defined
herein.

                                       A-1

<Page>

      4. PURCHASE AND SALE; REMARKETING UNDERWRITING FEE. Subject to the
terms and conditions and in reliance upon the representations and warranties
herein set forth or incorporated by reference herein and in the Remarketing
Agreement, the Remarketing Agent agrees to use its reasonable efforts to
remarket, in the manner set forth in Section 2(b) of the Remarketing
Agreement, the aggregate principal amount, as the case may be, of Securities
set forth in Schedule I hereto at a purchase price not less than 100% of the
[Minimum Initial Remarketing Price]
[aggregate principal amount of the Securities]. In connection therewith, the
registered holder or holders thereof agree, in the manner specified in
Section 5 hereof, to pay to the Remarketing Agent a Remarketing Fee equal to
an amount not exceeding 25 basis points (0.25%) of
[the Minimum Initial Remarketing Price] [such aggregate principal amount,]
payable by deduction from any amount received in connection from such
[Initial][Secondary] Remarketing in excess of the
[Minimum Initial Remarketing Price]
[aggregate principal amount of the Securities]. The right of each holder of
Securities to have Securities tendered for purchase shall be limited to the
extent set forth in the last sentence of Section 2(b) of the Remarketing
Agreement (which is incorporated by reference herein). As more fully provided
in Section 2(c) of the Remarketing Agreement (which is incorporated by
reference herein), the Remarketing Agent is not obligated to purchase any
Securities in the remarketing or otherwise, and neither the Company nor the
Remarketing Agent shall be obligated in any case to provide funds to make
payment upon tender of Securities for remarketing.

      5. DELIVERY AND PAYMENT. Delivery of payment for the remarketed
Securities and payment of the Remarketing Underwriting Fee shall be made on
the Remarketing Closing Date (which shall be the Purchase Contract Settlement
Date) at the location and time specified in Schedule I hereto, which date and
time may be postponed by agreement between the Remarketing Underwriter, the
Company and the [registered holder or holders thereof]. Delivery of payment
for the remarketed Securities shall be [to or upon the order of the
[registered holder or holders of the remarketed Securities] by certified or
official bank check or checks drawn on or by a New York Clearing House bank
and payable in immediately available funds][in immediately available funds by
wire transfer to an account or accounts designated by the [Company]
[registered holder or holders of the remarketed Securities] or, if the
remarketed Securities are represented by a Global Security, by any method of
transfer agreed upon by the Remarketing Underwriter and the depositary for
the Securities.

      [It is understood that any registered holder or, if the Securities are
represented by a Global Security, any beneficial owner, that has an account at
the Remarketing Underwriter and tenders its Securities through such account
will not be required to pay any fee or commission to the Remarketing
Underwriter.]

      If the Securities are not represented by a Global Security, certificates
for the Securities shall be registered in such names and denominations as the
Remarketing Underwriter may request not less than three full business days in
advance of the Remarketing Closing Date, and the Company and the [registered
holder or holders thereof] agree to have such certificates

                                       A-2

<Page>

available for inspection, packaging and checking by the Remarketing
Underwriter in New York, New York not later than 1:00 p.m. on the Business
Day prior to the Remarketing Closing Date.

      6. NOTICES. Unless otherwise specified, any notices, requests, consents
or other communications given or made hereunder or pursuant hereto shall be
made in writing or transmitted by any standard form of telecommunication,
including telephone, telegraph or telecopy, and confirmed in writing. All
written notices and confirmations of notices by telecommunication shall be
deemed to have been validly given or made when delivered or mailed,
registered or certified mail, return receipt requested and postage prepaid.
All such notices, requests, consents or other communications shall be
addressed as follows: if to the Company, to Affiliated Managers Group, Inc.,
600 Hale Street, Prides Crossing, MA 01965, Attention: Darrell W. Crate, with
a copy to Goodwin Procter LLP, Exchange Place, Boston, MA 02109-2881,
Attention: Martin Carmichael; if to the Remarketing Underwriter, to Merrill
Lynch, Pierce, Fenner & Smith Incorporated , 4 World Financial Center, North
Tower, New York, New York 10080, Attention: Investment Banking, with a copy
to Sidley Austin Brown & Wood LLP, 875 Third Avenue, New York, NY 10022,
Attention: L. Markus Wiltshire; and if to the Purchase Contract Agent, to
First Union National Bank, 12 East 49th Street, New York, New York 10017,
Attention: Corporate Trust NY 4040, or to such other address as any of the
above shall specify to the other in writing.

                                       A-3

<Page>

      If the foregoing is in accordance with your understanding of our
agreement, please sign and return to us the enclosed duplicate hereof,
whereupon this letter and your acceptance shall represent a binding agreement
among the Company, the Purchase Contract Agent and the Remarketing
Underwriter.

                                          Very truly yours,

                                          AFFILIATED MANAGERS GROUP, INC.

                                          By:
                                             ---------------------------------
                                             Name:
                                             Title:

CONFIRMED AND ACCEPTED:

MERRILL LYNCH & CO.
MERRILL LYNCH, PIERCE, FENNER & SMITH
            INCORPORATED

By:
   -----------------------------------
   Name:
   Title:

FIRST UNION NATIONAL BANK
not individually but solely as Purchase Contract
Agent and as attorney-in-fact for the holders
of the Purchase Contracts

By:
   -----------------------------------
   Name:
   Title:

                                       A-4

<Page>

                                                                      SCHEDULE I

Purchase Contract Agreement dated as of December 21, 2001 by and between
Affiliated Managers Group, Inc., a Delaware company, and First Union National
Bank, a national banking association

Pledge Agreement dated as of December 21, 2001 by and between Affiliated
Managers Group, Inc., a Delaware company, and First Union National Bank, as
Collateral Agent, Custodial Agent and Securities Intermediary, and as
Purchase Contract Agent

Registration Statement No. 333-74558

Aggregate Principal Amount of Securities:  $200,000,000 ($230,000,000 if the
underwriters' overallotment option is exercised)

Underwriting Agreement, dated as of December 18, 2001 between Affiliated
Managers Group, Inc. and Merrill Lynch & Co. and Merrill Lynch, Pierce,
Fenner & Smith Incorporated, Goldman Sachs & Co. and Morgan Stanley & Co.
Incorporated.

Remarketing Underwriting Fee:  0.25% (25 basis points)

Remarketing Closing Date, Time and Location: [Closing Date], [Time] and
[Location]

                                   SCH-I-1<Page>

                                                                  EXHIBIT 4.3.5

                                FOURTH AMENDMENT
                                     TO THE
                           THIRD RESTATED AND AMENDED
                      PUBLIC SERVICE COMPANY OF NEW MEXICO
                             PERFORMANCE STOCK PLAN

         THIS FOURTH AMENDMENT is made by the Public Service Company of New
Mexico effective upon the implementation of a holding company structure pursuant
to which PNM Resources, Inc. will become the parent holding company for Public
Service Company of New Mexico through a mandatory share exchange. The mandatory
share exchange presently is scheduled to occur on December 1 [31], 2001.

         WHEREAS, Public Service Company of New Mexico originally adopted the
Public Service Company of New Mexico Performance Stock Plan (the "Plan") as of
July 1, 1993 to provide certain key employees with an incentive to put forth
maximum effort to achieve a pattern of sustained growth for Public Service
Company of New Mexico;

         WHEREAS, the Plan has been restated three times, with the most recent
restatement being effective as of March 10, 1998;

         WHEREAS, the restated Plan has been amended three times, most recently
effective December 10, 2000;

         WHEREAS, Public Service Company of New Mexico reserved the right to
amend the Plan pursuant to Section 10.1 of the Plan; and

         WHEREAS, Public Service Company of New Mexico now desires to amend the
Plan to: (i) change the name of the Plan; (ii) make PNM Resources, Inc. the
sponsor of and participating employer in the Plan; and (iii) designate Public
Service Company of New Mexico as a participating employer.

         NOW, THEREFORE, Public Service Company of New Mexico does hereby amend
the Plan as follows:

         1.       The name of the Plan is hereby amended to read as follows:

                           THIRD RESTATED AND AMENDED
                   PNM RESOURCES, INC. PERFORMANCE STOCK PLAN

               (FORMERLY, THE PUBLIC SERVICE COMPANY OF NEW MEXICO
                             PERFORMANCE STOCK PLAN)

         2.       Article I of the Plan is hereby amended in its entirety to
read as follows:

                    The purpose of the PNM Resources, Inc. Performance Stock
         Plan (the "Plan") is to increase the proprietary interests in the
         Company of certain key employees with the intent of (i) fostering a
         strong incentive for such individuals to put forth maximum effort to
         achieve a pattern of sustained growth of the Company, and to perform in
         the best interests of the Company, its shareholders, customers and
         employees, (ii) retaining individuals who will put forth such efforts,
         and (iii) attracting the best available individuals to fulfill those
         positions in the future. The Plan was originally approved by the
         shareholders of Public Service Company of New Mexico on May 25, 1993,
         and was effective on July 1, 1993. The Plan was first amended on
         February 23, 1994, and was restated and amended effective January 1,
         1996 (the "First Restated and Amended Plan"). In 1997, the First
         Restated and Amended Plan was amended. The Second Restated and Amended
         Plan was approved and became effective on March 10, 1998 (the "Second
         Restatement"). Also, effective on March 10, 1998, Public Service
         Company of New Mexico made certain technical

<Page>

         corrections to the Second Restatement and, for administrative
         convenience, embodied the technical corrections in the form of a
         restatement (the "Third Restatement").

                    Effective on completion of a mandatory share exchange, PNM
         Resources, Inc. will become the parent holding company for Public
         Service Company of New Mexico and the Plan is hereby amended to reflect
         this new holding company structure.

         3.       Section 2.7 of the Plan is hereby amended in its entirety to
read as follows:

                     2.7    "COMPANY" means PNM Resources, Inc., or any
       affiliate of the Company that is authorized by the Board to adopt the
       Plan and which has adopted the Plan. Affiliates that adopted the Plan
       prior to the effective date of the Fourth Amendment with the consent of
       the Public Service Company of New Mexico board of directors, including
       Public Service Company of New Mexico, shall continue to participate in
       the Plan.

         4.       Section 2.23 of the Plan is hereby amended in its entirety to
read as follows:

                     2.23   "PLAN" means the PNM Resources, Inc. Performance
       Stock Plan, as adopted herein. The Plan was formerly known as the Public
       Service Company of New Mexico Performance Stock Plan.

         5.       Section 2.25 of the Plan is hereby amended in its entirety to
read as follows:

                     2.25   "PRESIDENT" shall mean the President of PNM
       Resources, Inc.

         6.       The purpose of this Fourth Amendment is to transfer
sponsorship of the Plan to PNM Resources, Inc. from the Public Service Company
of New Mexico. Any other provisions of the Plan which are inconsistent with this
transfer of sponsorship are hereby amended to the extent necessary to accomplish
this transfer.

         7.       This Fourth Amendment changes the name and sponsorship of the
Plan but the Plan is ongoing. Any individuals or entities serving in positions
of responsibility with respect to the Plan shall continue to serve as such,
subject to the provisions of the Plan. Similarly, any policies or procedures
previously adopted by such individuals or entities shall continue in full force
and effect.

         8.       This Fourth Amendment shall only amend the provisions of the
Plan referred to above, and those provisions not amended hereby shall be
considered in full force and effect. By the execution of this Fourth Amendment,
PNM Resources, Inc. agrees to serve as the sponsor of and a participating
employer in the Plan.

         IN WITNESS WHEREOF, Public Service Company of New Mexico has caused
this Fourth Amendment to be executed as of this 31 day of December, 2001.

                      PUBLIC SERVICE COMPANY OF NEW MEXICO

                      By: /s/ Alice A. Cobb
                         -------------------------------------------
                                   Senior Vice President, People
                                   Services and Development
                                   ---------------------------------

                      ACCEPTED:

                      PNM RESOURCES, INC.

                      By: /s/ Alice A. Cobb
                         -------------------------------------------
                                   Senior Vice President, People
                                   Services and Development
                                   ---------------------------------

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