EXHIBIT (a)(4)

Dear Shareholder:

     As you requested, we are enclosing a copy of the Van Kampen Senior Floating
Rate Fund ("Trust") Offer to Purchase 13,165,587 of its issued and outstanding
common shares of beneficial interest ("Common Shares") and the related Letter of
Transmittal (which together constitute the "Offer"). The Offer is at the net
asset value per Common Share ("NAV") determined as of 5:00 P.M. Eastern Time on
February 14, 2003, the expiration date of the Offer (unless extended). An "Early
Withdrawal Charge" will be imposed on most Common Shares accepted for payment
that have been held for less than one year. Please read carefully the enclosed
documents.

     If, after reviewing the information set forth in the Offer, you wish to
tender Common Shares for purchase by the Trust, please either follow the
instructions contained in the Offer to Purchase and related Letter of
Transmittal or, if your Common Shares are held of record in the name of a
broker, dealer or other nominee, contact such broker, dealer or nominee to
effect the tender for you.

     Neither the Trust nor its Board of Trustees is making any recommendation to
any holder of Common Shares as to whether to tender Common Shares. Each
shareholder is urged to consult his or her broker or tax adviser before deciding
whether to tender any Common Shares.

     The Trust's NAV from January 3, 2001 through January 3, 2003 ranged from a
high of $9.03 to a low of $7.36. On January 3, 2003 the NAV was $7.40. You can
obtain current NAV quotations from Van Kampen Funds Inc. by calling (800)
341-2911 between the hours of 7:00 A.M. and 7:00 P.M. Central Time, Monday
through Friday, except holidays. NAV quotes also may be obtained through the ICI
Pricing Service which will be released each Friday evening and published by the
Dow Jones Capital Markets Wire Service on each Friday; published in the New York
Times on each Saturday; published in the Chicago Tribune on each Sunday; and
published weekly in Barron's magazine. The Trust offers and sells its Common
Shares to the public on a continuous basis. The Trust is not aware of any
secondary market trading for the Common Shares.

     Should you have any questions on the enclosed material, please call Van
Kampen Funds Inc. at (800) 341-2911 during ordinary business hours. We
appreciate your continued interest in Van Kampen Senior Floating Rate Fund.

                                        Sincerely,

                                        VAN KAMPEN SENIOR FLOATING RATE FUND

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TO ENSURE PROCESSING OF YOUR REQUEST, A LETTER OF TRANSMITTAL OR A MANUALLY
SIGNED FACSIMILE OF IT (TOGETHER WITH ANY CERTIFICATES FOR COMMON SHARES AND ALL
OTHER REQUIRED DOCUMENTS) MUST BE RECEIVED BY THE DEPOSITARY ON OR BEFORE THE
EXPIRATION DATE (FEBRUARY 14, 2003).

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