AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON JULY 19, 2002
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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
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                                  SCHEDULE TO
                             TENDER OFFER STATEMENT
                   UNDER SECTION 14(d)(1) OR 13(e)(1) OF THE
                        SECURITIES EXCHANGE ACT OF 1934
                              (AMENDMENT NO.    )
                      VAN KAMPEN SENIOR FLOATING RATE FUND
                                (NAME OF ISSUER)

                      VAN KAMPEN SENIOR FLOATING RATE FUND
                      (NAME OF PERSON(S) FILING STATEMENT)

        Common Shares of Beneficial Interest, Par Value $0.01 per Share
                         (Title of Class of Securities)

                                   920960-101
                     (CUSIP Number of Class of Securities)

                              A. Thomas Smith III
                               Managing Director
                          Van Kampen Investments Inc.
                                1 Parkview Plaza
                                 P.O. Box 5555
                        Oakbrook Terrace, IL 60181-5555
                                 (630) 684-6000
      (Name, Address and Telephone Number of Person Authorized to Receive
      Notices and Communications on Behalf of Person(s) Filing Statement)

                                   Copies to:
                             Wayne W. Whalen, Esq.
                              Thomas A. Hale, Esq.
                Skadden, Arps, Slate, Meagher & Flom (Illinois)
                              333 W. Wacker Drive
                            Chicago, Illinois 60606
                                 (312) 407-0700

                           CALCULATION OF FILING FEE
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Transaction Valuation $123,780,197(a)       Amount of Filing Fees: $11,388.00(b)
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(a)  Calculated as the aggregate maximum purchase price to be paid for
     15,869,256 shares in the offer.

(b)  Calculated as .0092% of the Transaction Valuation.

 [ ]   Check box if any part of the fee is offset as provided by Rule 0-11(a)(2)
       and identify the filing with which the offsetting fee was previously
       paid. Identify the previous filing by registration statement number, or
       the Form or Schedule and the date of its filing.

     Amount Previously Paid:

     Form or Registration No.:

     Filing Party:

     Date Filed:

 [ ]   Check the box if the filing relates solely to preliminary communications
       made before the commencement of a tender offer.

 Check the appropriate boxes below to designate any transactions to which the
statement relates:

      [ ]   third-party tender offer subject to Rule 14d-1.

      [X]   issuer tender offer subject to Rule 13e-4.

      [ ]   going-private transaction subject to Rule 13e-3.

      [ ]   amendment to Schedule 13D under Rule 13d-2.

 [ ]   Check the following box if the filing is a final amendment reporting the
       results of the tender offer.
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ITEM 1. SUMMARY TERM SHEET.

     Reference is hereby made to the "Summary Term Sheet" of the Offer to
Purchase, dated July 19, 2002 (the "Offer to Purchase"), which is attached
hereto as Exhibit (a)(1)(ii) and incorporated herein by reference.

ITEM 2. SUBJECT COMPANY INFORMATION.

     (a) Name and Address. The name of the issuer is Van Kampen Senior Floating
Rate Fund, a non-diversified, closed-end management investment company organized
as a Massachusetts business trust (the "Trust"). The principal executive office
of the Trust is located at 1 Parkview Plaza, Oakbrook Terrace, IL 60181-5555.
The telephone number of the principal executive office of the Trust is (630)
684-6000.

     (b) Securities. The title of the securities being sought is common shares
of beneficial interest, par value $0.01 per share (the "Common Shares"). As of
July 12, 2002 there were approximately 48,088,655 Common Shares issued and
outstanding.

     (c) Trading Market and Price. The Common Shares are not currently traded
on an established trading market.

ITEM 3. IDENTITY AND BACKGROUND OF THE FILING PERSON.

     The name of the filing person is the Trust. The name, business address and
business telephone number of the Trust is Van Kampen Senior Floating Rate Fund
which is located at: 1 Parkview Plaza, Oakbrook Terrace, IL 60181-5555, and can
be reached by telephone at (630) 684-6000. The filing person is the subject
company.

ITEM 4. TERMS OF THE TRANSACTION.

     The Trust is seeking tenders for 15,869,256 Common Shares at the net asset
value per Common Share calculated on the day the tender offer expires, upon the
terms and subject to the conditions set forth in the Offer to Purchase and the
related Letter of Transmittal (which together with the Offer to Purchase
constitute the "Offer"). Tendering shareholders receive cash proceeds from the
tender of Common Shares of the Trust, or tendering shareholders may elect to
have the Trust's depositary invest the cash proceeds from the tender of Common
Shares of the Trust in shares of other investment companies advised by Van
Kampen Investment Advisory Corp. or Van Kampen Asset Management Inc. and
distributed by Van Kampen Funds Inc. as described in the Offer to Purchase and
related Letter of Transmittal. An "Early Withdrawal Charge" will be imposed on
most Common Shares accepted for payment that have been held for less than one
year. The scheduled expiration date is August 16, 2002, unless extended as
described in the Offer to Purchase (the later of August 16, 2002 or the date of
the extended expiration date is referred to as the "Expiration Date"). As
described in the Offer to Purchase, shareholders may withdraw Common Shares
tendered in the Offer at any time prior to 12:00 Midnight Eastern Time on the
Expiration Date or, if not yet accepted for payment, after September 13, 2002.
The procedures for tendering and withdrawing Common Shares, the manner in which
Common Shares will be accepted for payment, the Trust's intentions in the event
the Offer is oversubscribed and federal income tax consequences of the Offer are
described in the Offer to Purchase. The Trust is not aware of any Common Shares
to be purchased from any officer, trustee or affiliate of the Trust pursuant to
the Offer. Copies of the Offer to Purchase and the form of Letter of Transmittal
are attached hereto as Exhibit (a)(1)(ii) and Exhibit (a)(2), respectively and
are incorporated herein by reference.

ITEM 5. PAST CONTRACTS, TRANSACTIONS, NEGOTIATIONS AND AGREEMENTS.

     Reference is hereby made to Section 10 "Interest of Trustees and Executive
Officers; Transactions and Arrangements Concerning the Common Shares" and
Section 12 "Source and Amount of Funds" of the Offer to Purchase which is
incorporated herein by reference. Except as set forth therein, the Trust does
not know of any agreement, arrangement or understanding, whether or not legally
enforceable, between the Trust, any of the Trust's executive officers or
Trustees, any person controlling the Trust or any officer or director of any
corporation ultimately in control of the Trust and any other person with respect
to any securities of the Trust.

                                        2


ITEM 6. PURPOSE OF THE TRANSACTION AND PLANS OR PROPOSALS.

     Reference is hereby made to Section 7 "Purpose of the Offer," Section 8
"Plans or Proposals of the Trust," Section 10 "Interest of Trustees and
Executive Officers; Transactions and Arrangements Concerning the Common Shares,"
Section 11 "Certain Effects of the Offer," Section 12 "Source and Amount of
Funds" and Section 13 "Certain Information about the Trust" of the Offer to
Purchase, which are incorporated herein by reference. In addition, the Trust
regularly purchases and sells assets in its ordinary course of business. Except
as set forth above, the Trust has no plans or proposals which relate to or would
result in (a) an extraordinary transaction, such as a merger, reorganization or
liquidation, involving the Trust; (b) any purchase, sale or transfer of a
material amount of assets of the Trust; (c) any material change in the present
dividend rate or policy, or indebtedness or capitalization of the Trust; (d) any
change in the present Board of Trustees or management of the Trust, including,
but not limited to, any plans or proposals to change the number or the term of
Trustees, or to fill any existing vacancy on the Board of Trustees or to change
any material term of the employment contract of any executive officer of the
Trust; (e) any other material change in the Trust's corporate structure or
business, including any plans or proposals to make any changes in its investment
policy for which a vote would be required by Section 13 of the Investment
Company Act of 1940, as amended; (f) a class of equity securities of the Trust
to be delisted from a national securities exchange or to cease to be authorized
to be quoted on an inter-dealer quotation system of a registered national
securities association; (g) a class of equity security of the Trust becoming
eligible for termination of registration under the Investment Company Act of
1940, as amended; (h) the suspension of the Trust's obligation to file reports
pursuant to Section 15(d) of the Securities Exchange Act of 1934, as amended;
(i) the acquisition by any person of additional securities of the Trust or the
disposition of securities of the Trust; or (j) changes in the Trust's
declaration of trust, bylaws or instruments corresponding thereto or other
actions which may impede the acquisition of control of the Trust by any person.

ITEM 7. SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION.

     Reference is hereby made to Section 12 "Source and Amounts of Funds" of the
Offer to Purchase, which is incorporated herein by reference.

ITEM 8. INTEREST IN SECURITIES OF THE SUBJECT COMPANY.

     Reference is hereby made to Section 10 "Interest of Trustees and Executive
Officers; Transactions and Arrangements Concerning the Common Shares" of the
Offer to Purchase and the financial statements included as part of Exhibit
(a)(1)(ii) attached hereto, which are incorporated herein by reference. Except
as set forth therein, there have not been any transactions involving the Common
Shares of the Trust that were effected during the past 60 days by the Trust, any
executive officer or Trustee of the Trust, any person controlling the Trust, any
executive officer or director of any corporation ultimately in control of the
Trust or by any associate or subsidiary of any of the foregoing, including any
executive officer or director of any such subsidiary.

ITEM 9. PERSONS/ASSETS RETAINED, EMPLOYED, COMPENSATED OR USED.

     No persons have been employed, retained or are to be compensated by or on
behalf of the Trust to make solicitations or recommendations in connection with
the Offer.

ITEM 10. FINANCIAL INFORMATION.

     (a)-(b) Reference is hereby made to the financial statements included as
part of Exhibit (a)(1)(ii) attached hereto, which are incorporated herein by
reference.

                                        3


ITEM 11. ADDITIONAL INFORMATION.

     (a)(1) Reference is hereby made to Section 10 "Interests of Trustees and
Executive Officers; Transactions and Arrangements Concerning the Common Shares"
of the Offer to Purchase which is incorporated herein by reference.

     (a)(2) through (a)(5) Not applicable.

     (b) The Offer to Purchase, attached hereto as Exhibit (a)(1)(ii), is
incorporated herein by reference in its entirety.

ITEM 12. MATERIAL TO BE FILED AS EXHIBITS.

<Table>
                 
       (a)(1)(i)    Advertisement printed in The Wall Street Journal.
            (ii)    Offer to Purchase (including Financial Statements).
          (a)(2)    Form of Letter of Transmittal (including Guidelines for
                    Certification of Taxpayer Identification Number).
       (a)(3)(i)    Form of Letter to Brokers, Dealers, Commercial Banks, Trust
                    Companies and Other Nominees.
            (ii)    Form of Letter to Clients of Brokers, Dealers, Commercial
                    Banks, Trust Companies and Other Nominees.
           (iii)    Form of Letter to Selling Group Members.
            (iv)    Form of Operations Notice.
          (a)(4)    Form of Letter to Shareholders who have requested Offer to
                    Purchase.
          (a)(5)    Text of Press Release dated July 19, 2002.
          (b)(1)    Fourth Amendment and Restatement of Credit Agreement between
                    Van Kampen Prime Rate Income Trust, Van Kampen Senior
                    Floating Rate Fund, Various Financial Institutions and Bank
                    of America, N.A., as agent, dated as of November 9, 2001.
                    Previously filed as Exhibit (b)(1) to the Trust's Form TO
                    via EDGAR on April 19, 2002.
          (d)(1)    Investment Advisory Agreement between Van Kampen Senior
                    Floating Rate Fund and Van Kampen Investment Advisory Corp.,
                    dated as of December 19, 1997. Previously filed as Exhibit
                    (d)(1) to the Trust's Form TO via EDGAR on April 19, 2002.
          (d)(2)    Administration Agreement between Van Kampen Senior Floating
                    Rate Fund and Van Kampen Investments Inc., dated as of
                    December 19, 1997. Previously filed as Exhibit (d)(2) to the
                    Trust's Form TO via EDGAR on April 19, 2002.
          (d)(3)    Offering Agreement between Van Kampen Senior Floating Rate
                    Fund and Van Kampen Funds Inc., dated as of December 19,
                    1997. Previously filed as Exhibit (d)(3) to the Trust's Form
                    TO via EDGAR on April 19, 2002.
          (d)(4)    Service Plan of Van Kampen Senior Floating Rate Fund.
                    Previously filed as Exhibit (d)(4) to the Trust's Form TO
                    via EDGAR on April 19, 2002.
         (g)-(h)    Not applicable.
</Table>

ITEM 13. INFORMATION REQUIRED BY SCHEDULE 13E-3.

     Not applicable.

                                        4


                                   SIGNATURE

     After due inquiry and to the best of my knowledge and belief, I certify
that the information set forth in this statement is true, complete and correct.

                                  VAN KAMPEN SENIOR FLOATING RATE FUND

<Table>
                                           
Dated: July 19, 2002                          /s/  A. THOMAS SMITH III
                                              -----------------------------------------------------------
                                              A. Thomas Smith III,
                                              Vice President and Secretary
</Table>

                                        5


                                 EXHIBIT INDEX

<Table>
<Caption>
      EXHIBIT                                DESCRIPTION
      -------                                -----------
                  
    (a)(1)(i)        Advertisement printed in The Wall Street Journal
    (a)(1)(ii)       Offer to Purchase (including Financial Statements)
    (a)(2)           Form of Letter of Transmittal (including Guidelines for
                     Certification of Tax Identification Number)
    (a)(3)(i)        Form of Letter to Brokers, Dealers, Commercial Banks, Trust
                     Companies and Other Nominees
    (a)(3)(ii)       Form of Letter to Clients of Brokers, Dealers, Commercial
                     Banks, Trust Companies and Other Nominees
    (a)(3)(iii)      Form of Letter to Selling Group Members
    (a)(3)(iv)       Form of Operations Notice
    (a)(4)           Form of Letter to Shareholders who have requested Offer to
                     Purchase
    (a)(5)           Text of Press Release dated July 19, 2002
    (b)(1)           Fourth Amendment and Restatement of Credit Agreement between
                     Van Kampen Prime Rate Income Trust, Van Kampen Senior
                     Floating Rate Fund, Various Financial Institutions and Bank
                     of America, N.A., as agent, dated as of November 9, 2001.
                     Previously filed as Exhibit (b)(1) to the Trust's Form TO
                     via EDGAR on April 19, 2002.
    (d)(1)           Investment Advisory Agreement between Van Kampen Senior
                     Floating Rate Fund and Van Kampen Investment Advisory Corp.,
                     dated as of December 19, 1997. Previously filed as Exhibit
                     (d)(1) to the Trust's Form TO via EDGAR on April 19, 2002.
    (d)(2)           Administration Agreement between Van Kampen Senior Floating
                     Rate Fund and Van Kampen Investments Inc., dated as of
                     December 19, 1997. Previously filed as Exhibit (d)(2) to the
                     Trust's Form TO via EDGAR on April 19, 2002.
    (d)(3)           Offering Agreement between Van Kampen Senior Floating Rate
                     Fund and Van Kampen Funds Inc., dated as of December 19,
                     1997. Previously filed as Exhibit (d)(3) to the Trust's Form
                     TO via EDGAR on April 19, 2002.
    (d)(4)           Service Plan of Van Kampen Senior Floating Rate Fund.
                     Previously filed as Exhibit (d)(4) to the Trust's Form TO
                     via EDGAR on April 19, 2002.
</Table>