EXHIBIT (6)(b)

                              AMENDMENT NUMBER ONE
                                     TO THE
                          INVESTMENT ADVISORY AGREEMENT

This Amendment Number One, dated November 1, 2004, to the Investment Advisory
Agreement, dated May 31, 1997 (the "Agreement"), by and between Van Kampen Trust
for Investment Grade Municipals (the "Fund"), a Massachusetts business trust
(the "Trust"), and Van Kampen Asset Management (the "Adviser," successor in
interest of Van Kampen Investment Advisory Corp.), a Delaware statutory trust,
hereby amends the terms and conditions of the Agreement in the manner specified
herein.

                                   WITNESSETH

WHEREAS, the Board of Trustees of the Fund at a meeting held on September 23,
2004 has approved a reduction in the investment management fee payable by the
Fund to the Adviser; and

WHEREAS, the parties desire to amend and restate Section 2.(a) of the Agreement
relating to the investment management fee.

NOW THEREFORE, in consideration of the foregoing and the mutual covenants and
agreements hereinafter contained, the parties hereby agree to amend the
Agreement, as follows:

Section 2.(a) of the Agreement is hereby deleted in its entirety and replaced
with the following:

2.(a) Fee. For the services and facilities described in Section 1, the Fund will
accrue daily and pay to the Adviser at the end of each calendar month an
investment management fee equal to 0.55% 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).

            IN WITNESS WHEREOF, the parties have caused this Agreement to be
executed as of the day and year first above written.

VAN KAMPEN TRUST FOR                          VAN KAMPEN ASSET MANAGEMENT
INVESTMENT GRADE MUNICIPALS

By: /s/ Ronald E. Robison                     By: /s/ Edward C. Wood, III
    --------------------------------------        -----------------------
    Ronald E. Robison                             Edward C. Wood, III
    Executive Vice President and Principal        Managing Director
    Executive Officer