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                                                                    Exhibit 4(m)

                          INVESTMENT ADVISORY AGREEMENT

         AGREEMENT made as of June 16, 2000, by and between MERCURY ASSET
MANAGEMENT MASTER TRUST, a Delaware business trust (hereinafter referred to as
the "Trust") on behalf of its series MERCURY MASTER SELECT GROWTH PORTFOLIO (the
"Portfolio") and MERCURY ASSET MANAGEMENT US, (hereinafter referred to as the
"Investment Adviser"), a division of Fund Asset Management, L.P., a Delaware
limited partnership.


                              W I T N E S S E T H:

         WHEREAS, the Trust is engaged in business as an open-end management
investment company registered under the Investment Company Act of 1940, as
amended (hereinafter referred to as the "Investment Company Act"); and

         WHEREAS, the Trustees of the Trust (the "Trustees") are authorized to
establish separate series relating to separate portfolios of securities, each of
which may offer separate classes of shares; and

         WHEREAS, the Trustees have established and designated the Portfolio as
a series of the Trust; and

         WHEREAS, the Investment Adviser is engaged principally in rendering
management and investment advisory services and is registered as an investment
adviser under the Investment Advisers Act of 1940; and

         WHEREAS, the Trust desires to retain the Investment Adviser to provide
management and investment advisory services to the Portfolio in the manner and
on the terms hereinafter set forth; and

         WHEREAS, the Investment Adviser is willing to provide management and
investment advisory services to the Portfolio on the terms and conditions
hereafter set forth;

         NOW, THEREFORE, in consideration of the premises and the covenants
hereinafter contained, the Trust and the Investment Adviser hereby agree as
follows:


                                    ARTICLE I


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                        DUTIES OF THE INVESTMENT ADVISER

         The Trust hereby employs the Investment Adviser to act as a manager and
investment adviser of the Portfolio and to furnish, or arrange for affiliates to
furnish, the management and investment advisory services described below,
subject to the policies of, review by and overall control of the Trustees, for
the period and on the terms and conditions set forth in this Agreement. The
Investment Adviser hereby accepts such employment and agrees during such period,
at its own expense, to render, or arrange for the rendering of, such services
and to assume the obligations herein set forth for the compensation provided for
herein. The Investment Adviser and its affiliates shall for all purposes herein
be deemed to be independent contractors and shall, unless otherwise expressly
provided or authorized, have no authority to act for or represent the Trust or
the Portfolio in any way or otherwise be deemed agents of the Trust or the
Portfolio.

                  (a) Management Services. The Investment Adviser shall perform
         (or arrange for the performance of) the management and administrative
         services necessary for the operation of the Trust and the Portfolio.
         The Investment Adviser shall provide the Trust and the Portfolio with
         office space, facilities, equipment and necessary personnel and such
         other services as the Investment Adviser, subject to review by the
         Trustees, shall from time to time determine to be necessary or useful
         to perform its obligations under this Agreement. The Investment Adviser
         shall also, on behalf of the Trust and the Portfolio, conduct relations
         (or arrange for the conduct of such relations) with custodians,
         depositories, transfer agents, dividend disbursing agents, other
         shareholder servicing agents, accountants, attorneys, underwriters,
         brokers and dealers, corporate fiduciaries, insurers, banks and such
         other persons in any such other capacity deemed to be necessary or
         desirable. The Investment Adviser shall generally monitor (or arrange
         for the monitoring of) the Trust's and the Portfolio's compliance with
         investment policies and restrictions as set forth in the Registration
         Statement of the Trust filed with the Securities and Exchange
         Commission under the Investment Company Act, as amended from time to
         time (the "Registration Statement"). The Investment Adviser shall make
         reports (or arrange for the making of such reports) to the Trustees of
         its performance of obligations hereunder and furnish advice and
         recommendations with respect to such other aspects of the business and
         affairs of the Portfolio as it shall determine to be desirable.

                  (b) Investment Advisory Services. The Investment Adviser shall
         provide (or arrange for the provision of) the Trust with such
         investment research, advice and supervision as the latter may from time
         to time consider necessary for the proper supervision of the assets of
         the Portfolio, shall furnish (or arrange for the furnishing of)
         continuously an investment program for the Portfolio and shall
         determine (or arrange for the determination of) from time to time which
         securities shall be purchased, sold or exchanged and what portion of
         the assets of the Portfolio shall be held in the various securities and
         other financial instruments in which the Portfolio invests or cash,
         subject always to the restrictions of the Declaration of Trust and
         By-Laws of the Trust, as amended from time to time, the provisions of
         the Investment Company Act and the statements relating to the
         Portfolio's investment objectives,

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         investment policies and investment restrictions as the same are set
         forth in the Trust's current Registration Statement. The Investment
         Adviser shall make decisions (or arrange for the making of such
         decisions) for the Trust as to the manner in which voting rights,
         rights to consent to corporate action and any other rights pertaining
         to the Portfolio's portfolio securities shall be exercised. Should the
         Trustees at any time, however, make any definite determination as to
         investment policy and notify the Investment Adviser thereof in writing,
         the Investment Adviser shall be bound by such determination for the
         period, if any, specified in such notice or until similarly notified
         that such determination has been revoked. The Investment Adviser shall
         take, on behalf of the Portfolio, all actions (or arrange for the
         taking of all such actions) which it deems necessary to implement the
         investment policies determined as provided above, and in particular to
         place all orders for the purchase or sale of portfolio securities for
         the Portfolio's account with brokers or dealers selected by it, and to
         that end, the Investment Adviser is authorized as the agent of the
         Trust to give instructions to the custodian of the Portfolio as to
         deliveries of securities and payments of cash for the account of the
         Portfolio. In connection with the selection of such brokers or dealers
         and the placing of such orders with respect to assets of the Portfolio,
         the Investment Adviser is directed at all times to seek to obtain
         execution and price within the policy guidelines determined by the
         Trustees and set forth in the then current Registration Statement.
         Subject to this requirement and the provisions of the Investment
         Company Act, the Securities Exchange Act of 1934, as amended, and other
         applicable provisions of law, the Investment Adviser may select brokers
         or dealers with which it or the Trust is affiliated.

                  (c) Sub-Advisers. In carrying out its responsibilities
         hereunder, the Investment Adviser may employ, retain or otherwise avail
         itself of the services of other persons or entities (including without
         limitation, affiliates of the Investment Adviser), on such terms as the
         Investment Adviser shall determine to be necessary, desirable or
         appropriate. However, if the Investment Adviser chooses to retain or
         avail itself of the services of another person or entity to manage
         assets of the Portfolio, or any portion thereof as determined by the
         Investment Adviser such other person or entity must be (i) retained at
         the Investment Adviser's own cost and expense and (ii) retained subject
         to the requirements of Section 15 of the Investment Company Act.
         Retention of one or more sub-advisers, or the employment or retention
         of other persons or entities to perform services, shall in no way
         reduce the responsibilities or obligations of the Investment Adviser
         under this Agreement and the Investment Adviser shall be responsible
         for all acts and omissions of such sub-advisers, or other persons or
         entities, in connection with the performance of the Investment
         Adviser's duties hereunder.

                  (d) Notice Upon Change in Partners of the Investment Adviser.
         The Investment Adviser is a division of a limited partnership and its
         limited partner is Merrill Lynch & Co., Inc. and its general partner is
         Princeton Services, Inc. The Investment Adviser will notify the Trust
         of any change in the membership of the partnership within a reasonable
         time after such change.

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                                   ARTICLE II
                       ALLOCATION OF CHARGES AND EXPENSES

                  (a) The Investment Adviser. The Investment Adviser assumes and
         shall pay, or cause its affiliate to pay, for maintaining the staff and
         personnel necessary to perform its obligations under this Agreement,
         and shall, at its own expense, provide the office space, facilities and
         necessary personnel which it is obligated to provide under Article I
         hereof. The Investment Adviser shall pay, or cause its affiliate to
         pay, compensation of all Officers of the Trust and all Trustees of the
         Trust who are affiliated persons of the Investment Adviser or any
         sub-adviser, or of an affiliate of the Investment Adviser or any
         sub-adviser.

                  (b) The Trust. The Trust assumes and shall pay or cause to be
         paid all other expenses of the Trust and the Portfolio (except for the
         expenses paid by Mercury Funds Distributor division of Princeton Funds
         Distributor, Inc. (the "Distributor")), including, without limitation:
         taxes, expenses for legal and auditing services, costs of printing
         proxies, shareholder reports, copies of the Registration Statement,
         charges of the custodian, any sub-custodian and transfer agent,
         expenses of portfolio transactions, expenses of redemption of shares,
         Securities and Exchange Commission fees, expenses of registering the
         shares under Federal, state and foreign laws, fees and actual
         out-of-pocket expenses of Trustees who are not affiliated persons of
         the Investment Adviser or any sub-adviser, or of an affiliate of the
         Investment Adviser or any sub-adviser, accounting and pricing costs
         (including the daily calculation of the net asset value), insurance,
         interest, brokerage costs, litigation and other extraordinary or
         non-recurring expenses, and other expenses properly payable by the
         Trust or the Portfolio. It is also understood that the Trust shall
         reimburse the Investment Adviser or an affiliate of the Investment
         Adviser for its costs in providing accounting services to the Trust and
         the Portfolio. The Distributor will pay certain of the expenses of the
         Portfolio incurred in connection with the continuous offering of shares
         of beneficial interest of the Portfolio.


                                   ARTICLE III
                     COMPENSATION OF THE INVESTMENT ADVISER

         Management and Investment Advisory Fee. For the services rendered, the
facilities furnished and expenses assumed by the Investment Adviser, the
Portfolio shall pay to the Investment Adviser at the end of each calendar month
a fee based upon the average daily value of the net assets of the Portfolio, as
determined and computed in accordance with the description of the determination
of net asset value contained in the Registration Statement, at the annual rate
of 0.50% of the average daily net assets of the Portfolio, commencing on the day
following effectiveness hereof. If this Agreement becomes effective subsequent
to the first day of a month or shall terminate before the last day of a month,
compensation for that part of the month this Agreement is in effect shall be
prorated in a manner consistent with the calculation of the fee as set forth
above. Payment of the Investment Adviser's compensation for the preceding month
shall be made as promptly as possible after

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completion of the computations contemplated above. During any period when the
determination of net asset value is suspended by the Trustees, the net asset
value of a share as of the last business day prior to such suspension shall for
this purpose be deemed to be the net asset value at the close of each succeeding
business day until it is again determined.


                                   ARTICLE IV
                LIMITATION OF LIABILITY OF THE INVESTMENT ADVISER

         The Investment Adviser shall not be liable for any error of judgment or
mistake of law or for any loss arising out of any investment or for any act or
omission in the management of the Trust and the Portfolio, except for willful
misfeasance, bad faith or gross negligence in the performance of its duties, or
by reason of reckless disregard of its obligations and duties hereunder. As used
in this Article IV, the term "Investment Adviser" shall include any affiliates
of the Investment Adviser performing services for the Trust or the Portfolio
contemplated hereby and partners, directors, officers and employees of the
Investment Adviser and such affiliates.


                                    ARTICLE V
                      ACTIVITIES OF THE INVESTMENT ADVISER

         The services of the Investment Adviser to the Trust and the Portfolio
are not to be deemed to be exclusive, and the Investment Adviser and each
affiliate is free to render services to others. It is understood that Trustees,
officers, employees and shareholders of the Trust and the Portfolio are or may
become interested in the Investment Adviser and its affiliates, as directors,
officers, employees, partners and shareholders or otherwise, and that the
Investment Adviser and directors, officers, employees, partners and shareholders
of the Investment Adviser and its affiliates are or may become similarly
interested in the Trust or the Portfolio as shareholders or otherwise.


                                   ARTICLE VI
                   DURATION AND TERMINATION OF THIS AGREEMENT

         This Agreement shall become effective as of the date first above
written, and shall remain in force for two years thereafter, and thereafter
continue from year to year, but only so long as such continuance is specifically
approved at least annually by (i) the Trustees, or by the vote of a majority of
the outstanding voting securities of the Portfolio, and (ii) a majority of those
Trustees who are not parties to this Agreement or interested persons of any such
party cast in person at a meeting called for the purpose of voting on such
approval.

         This Agreement may be terminated at any time, without the payment of
any penalty, by the Trustees or by the vote of a majority of the outstanding
voting securities of the Portfolio, or by the

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Investment Adviser, on sixty days' written notice to the other party. This
Agreement shall automatically terminate in the event of its assignment.


                                   ARTICLE VII
                          AMENDMENTS OF THIS AGREEMENT

         This Agreement may be amended by the parties only if such amendment is
specifically approved by (i) the vote of a majority of outstanding voting
securities of the Portfolio, and (ii) a majority of those Trustees who are not
parties to this Agreement or interested persons of any such party cast in person
at a meeting called for the purpose of voting on such approval.


                                  ARTICLE VIII
                          DEFINITIONS OF CERTAIN TERMS

         The terms "vote of majority of the outstanding voting securities,"
"assignment," "affiliated person" and "interested person," when used in this
Agreement, shall have the respective meanings specified in the Investment
Company Act and the Rules and Regulations thereunder, subject, however, to such
exemptions as may be granted by the Securities and Exchange Commission under
said Act.


                                   ARTICLE IX
                                  GOVERNING LAW

         This Agreement shall be construed in accordance with laws of the State
of New York and the applicable provisions of the Investment Company Act. To the
extent that the applicable laws of the State of New York, or any of the
provisions herein, conflict with the applicable provisions of the Investment
Company Act, the latter shall control.


                                    ARTICLE X
                   LIMITATION OF OBLIGATIONS OF THE PORTFOLIO

         The obligations of the Portfolio shall be limited to the assets of the
Portfolio, shall be separate from the obligations of any other series of the
Trust, and the Portfolio shall not be liable for the obligations of any other
series of the Trust.



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         IN WITNESS WHEREOF, the parties hereto have executed and delivered this
Agreement as of the date first above written. This Agreement may be executed by
the parties hereto on any number of counterparts, all of which together shall
constitute one and the same instrument.



                               MERCURY ASSET MANAGEMENT MASTER
                               TRUST on behalf of its series, MERCURY MASTER
                               SELECT GROWTH PORTFOLIO


                               By: /s/ DONALD C. BURKE
                                   ------------------------------------------
                               Title: Vice President and Treasurer


                               MERCURY ASSET MANAGEMENT US, a division
                               of Fund Asset Management, L.P.

                               By: PRINCETON SERVICES, INC.,
                                   GENERAL PARTNER

                               By: /s/ TERRY K. GLENN
                                   ------------------------------------------
                               Title: Executive Vice President and Director




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