EXHIBIT 6(a)

                         INVESTMENT ADVISORY AGREEMENT

THIS INVESTMENT ADVISORY AGREEMENT, dated as of May 31, 1997 (the "Agreement"),
by and between VAN KAMPEN AMERICAN CAPITAL MUNICIPAL TRUST (the "Fund"), a
Massachusetts business trust (the "Trust"), and VAN KAMPEN AMERICAN CAPITAL
INVESTMENT ADVISORY CORP. (the "Adviser"), a Delaware corporation.

1. (a) RETENTION OF ADVISER BY FUND. Subject to the terms and conditions set
forth herein, the Fund hereby employs the Adviser to act as the investment
adviser for and to manage the investment and reinvestment of the assets of the
Fund in accordance with the Fund's investment objective and policies and
limitations, and to administer its affairs to the extent requested by, and
subject to the review and supervision of, the Board of Trustees of the Fund for
the period and upon the terms herein set forth. The investment of funds shall be
subject to all applicable restrictions of applicable law and of the Declaration
of Trust and By-laws of the Trust, and resolutions of the Board of Trustees of
the Fund as may from time to time be in force and delivered or made available to
the Adviser.

   (b) ADVISER'S ACCEPTANCE OF EMPLOYMENT. The adviser accepts such employment
and agrees during such period to render such services, to supply investment
research and portfolio management (including without limitation the selection of
securities for the Fund to purchase, hold or sell and the selection of brokers
through whom the Fund's portfolio transactions are executed, in accordance with
the affairs of the Fund, to furnish offices and necessary facilities and
equipment to the Fund, to provide administrative services for the Fund, to
render periodic reports to the Board of Trustees of the Fund, and to permit any
of its officers or employees to serve without compensation as trustees or
officers of the Fund if elected to such positions.

   (c) ESSENTIAL PERSONNEL. For a period of one year commencing on the effective
date of this Agreement, the Adviser and the Fund agree that the retention of (i)
the chief executive officer, president, chief financial officer and secretary of
the Adviser and (ii) each director, officer and employee of the Adviser or any
of its Affiliates (as defined in the Investment Company Act of 1940, as amended
(the "1940 Act")) who serves as an officer of the Fund (each person referred to
in (i) or (ii) hereinafter being referred to as an "Essential Person"), in his
or her current capacities, is in the best interest of the Fund and the Fund's
shareholders. In connection with the Adviser's acceptance of employment
hereunder, the Adviser hereby agrees and covenants for itself and on behalf of
its Affiliates that neither the Adviser nor any of its Affiliates shall make any
material or significant personnel changes or replace or seek to replace any
Essential Person or cause to be replaced any Essential Person, in each case
without first informing the Board of Trustees of the Fund in a timely manner. In
addition, neither the Adviser nor any Affiliate of the Adviser shall change or
seek to change or cause to be changed, in any material respect, the duties and
responsibilities of any Essential Person, in each case without first informing
the Board of Trustees of the Fund in a timely manner.





   (d) INDEPENDENT CONTRACTOR. The Advisor shall be deemed to be an independent
contractor under this Agreement and, unless otherwise expressly provided or
authorized, shall have no authority to act for or represent the Fund in any way
or otherwise be deemed as agent of the Fund.

   (e) NON-EXCLUSIVE AGREEMENT. The services of the Adviser to the Fund under
this Agreement are not to be deemed exclusive, and the Adviser shall be free to
render similar services or other services to others so long as its services
hereunder are not impaired thereby.

2. (a) FEE. For the services and facilities described in Section 1, the Fund
will accrue daily and pay to the Advisor at the end of each calendar month an
investment management fee equal to seventy one-hundredths of one percent (.70 of
1%) of the average daily managed assets of the Fund (which for purposes of
determining such fee, shall mean the average daily value of the Fund, minus the
sum of accrued liability other than the aggregate amount of any borrowings
undertaken by the Fund).

   (b) DETERMINATION OF NET ASSET VALUE. The net asset value of the Fund shall
be calculated as of the close of the New York Stock Exchange on the last day the
Exchange is open for trading in each calendar week or such other time or times
as the trustees may determine in accordance with the provisions of applicable
law and the Declaration of Trust and By-Laws of the Trust, and resolutions of
the Board of Trustees of the Fund as from time to time in force. For the purpose
of the foregoing computations, on each such day when net asset value is not
calculated, the net asset value of a share of beneficial interest of the Fund
shall be deemed to be the net asset value of such share as of the close of
business of the last day on which such calculation was made.

   (c) PRORATION. For the month and year in which this Agreement becomes
effective or terminates, there shall be an appropriate proration of the
Adviser's fee on the basis of the number of days that the Agreement is in effect
during such month and year, respectively.

3. EXPENSES. In addition to the fee of the Adviser, the Fund shall assume and
pay any expenses for services rendered by a custodian for the safekeeping of the
Fund's securities or other property, for keeping its books of account, for any
other charges of the custodian and for calculating the net asset value of the
Fund as provided above. The Adviser shall not be required to pay, and the Fund
shall assume and pay, the charges and expenses of its operations, including
compensation of the trustees (other than those who are interested persons of the
Adviser), charges and expenses of independent accountants, of legal counsel and
of any transfer or dividend disbursing agent, costs of acquiring and disposing
of portfolio securities, cost of listing shares of the New York Stock Exchange
or other exchange, interest (if any) on obligations incurred by the Fund, costs
of share certificates, membership dues in the Investment Company Institute or
any similar organization, costs of reports and securities laws, miscellaneous
expenses and all taxes and fees to federal, state or other governmental agencies
on account of the registration of securities issues by the Fund, filing of
corporate documents or otherwise. The Fund shall not pay or incur any obligation
for any management or administrative expenses for which


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the Fund intends to seek reimbursement from the Adviser without first obtaining
the written approval of the Adviser. The Adviser shall arrange, if desired by
the Fund, for officers or employees of the Adviser to serve, without
compensation from the Fund, as trustees, officers or agents of the Fund if duly
elected or appointed to such positions and subject to their individual consent
and to any limitations imposed by the law.

4. INTERESTED PERSONS. Subject to applicable statutes and regulations, it is
understood that trustees, officers, shareholders and agents of the Fund are or
may be interested in the Adviser as directors, officers, shareholders, agents or
otherwise and that the directors, officers, shareholders and agents of the
Adviser may be interested in the Fund as trustees, officers, shareholders,
agents or otherwise.

5. LIABILITY. The Adviser shall not be liable for any error of judgment or of
law, or for any loss suffered by the Fund in connection with the matters in
which this Agreement relates, except a loss resulting from willful misfeasance,
bad faith or gross negligence on the part of the Adviser in the performance of
its obligations and duties, or by reason of its reckless disregard of its
obligations and duties under this Agreement.

6. (a) TERM. This Agreement shall become effective on the date hereof and shall
remain in full force until May 31, 1999 unless sooner terminated as hereinafter
provided. This Agreement shall continue in force from year to year thereafter,
but only for so long as such continuance is specifically approved as least
annually, in the manner required by the 1940 Act.

   (b) TERMINATION. This Agreement shall automatically terminate in the event of
its assignment. This Agreement may be terminated at any time without the payment
of any penalty by the Fund or by the Adviser on sixty (60) days written notice
to the other party. The Fund may effect termination by action of the Board of
Trustees or by vote of a majority of the outstanding shares of stock of the
Fund, accompanied by appropriate notice. This Agreement may be terminated at any
time without the payment of any penalty and without advance notice by the Board
of Trustees or by vote of a majority of the outstanding shares of the Fund in
the event that it shall have been established by a court of competent
jurisdiction that the Adviser or any officer or director of the Adviser has
taken any action which results in a breach of the covenants of the Adviser set
forth herein.

   (c) PAYMENT UPON TERMINATION. Termination of this Agreement shall not affect
the right of the Adviser to receive payment on any unpaid balance of the
compensation described in Section 2 earned prior to such termination.

7. SEVERABILITY. If any provision of this Agreement shall be held or made
invalid by a court decision, statute, rule or otherwise, the remainder shall not
thereby affected.

8. NOTICES. Any notice under this Agreement shall be in writing, addressed and
delivered or mailed, postage prepaid, to the other party at such address as such
other party may designate for the receipt of such notice.

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9. DISCLAIMER. The Adviser acknowledges and agrees that, as provided by Section
5.5 of the Declaration of Trust of the Trust, the shareholders, trustees,
officers, employees and other agents of the Trust and the Fund shall not
personally be bound by or liable hereunder, nor shall resort be had to their
private property for the satisfaction of any obligation or claim hereunder.

10. GOVERNING LAW. All questions concerning the validity, meaning and effect of
this Agreement shall be determined in accordance with the laws (without giving
effect to the conflict-of-law principles thereof) of the State of Delaware
applicable to contracts made and to be performed in that state.

11. NAME. In connection with its employment hereunder, the Adviser hereby agrees
and covenants not to change its name without the prior consent of the Board of
Trustees of the Fund.

IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be executed
by their officers designated below on the day and year first above written.

VAN KAMPEN AMERICAN CAPITAL         VAN KAMPEN AMERICAN CAPITAL
INVESTMENT ADVISORY CORP.           MUNICIPAL TRUST

By:    /s/ Dennis J. McDonnell      By:      /s/ Ronald A. Nyberg
     ---------------------------            ----------------------------------
Name:  Dennis J. McDonnell          Name:    Ronald A. Nyberg
Title: President                    Title:   Secretary


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