UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                  SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934
                               (Amendment No. __)

Filed by the Registrant [X]

Filed by a Party other than the Registrant [ ]

Check the appropriate box:

[ ]  Preliminary Proxy Statement

[ ]  Confidential, for Use of the Commission Only (as permitted by Rule
     14a-6(e)(2))

[ ]  Definitive Proxy Statement

[X]  Definitive Additional Materials

[ ]  Soliciting Material Pursuant to Section 240.14a-11(c) or Section
     240.14a-12

                              AIM INVESTMENT FUNDS
                (Name of Registrant as Specified In Its Charter)

________________________________________________________________________________
    (Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

[X]  No fee required.

[ ]  Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.

     1) Title of each class of securities to which transaction applies:

     ___________________________________________________________________________

     2) Aggregate number of securities to which transaction applies:

     ___________________________________________________________________________

     3) Per unit price or other underlying value of transaction computed
     pursuant to Exchange Act Rule 0-11 (set forth the amount on which the
     filing fee is calculated and state how it was determined):

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     4) Proposed maximum aggregate value of transaction:

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     5) Total fee paid:

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[ ]  Fee paid previously with preliminary materials.

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

     1) Amount Previously Paid:

     ___________________________________________________________________________

     2) Form, Schedule or Registration Statement No.:

     ___________________________________________________________________________

     3) Filing Party:

     ___________________________________________________________________________

     4) Date Filed:

     ___________________________________________________________________________



PROXY VOTING INFORMATION

A proxy statement was mailed on or about January 31, 2007 to shareholders of
record as of the close of business on January 22, 2007, for the funds listed
below. The purpose of the proxy statement is to request approval of an Agreement
and Plan of Reorganization or Plan of Reorganization, as applicable. Each proxy
statement contains disclosure information about the proposal for which votes are
being solicited. You can also access your fund's proxy statement, common
questions regarding your fund's proposal, prospectus, and annual report by
clicking on the fund name listed below.

         -  AIM Advantage Health Sciences Fund

         -  AIM Opportunities I Fund

         -  AIM Opportunities II Fund

         -  AIM Opportunities III Fund

- --------------------------------------------------------------------------------

HOW TO VOTE

You may cast your vote by any of the following methods. HOWEVER YOU CHOOSE TO
VOTE, IT IS IMPORTANT THAT YOU VOTE NOW TO SAVE THE EXPENSE OF ADDITIONAL
SOLICITATIONS.

BY INTERNET
[Computer
Photo]

You may vote your shares at www.proxyweb.com unless your shares are held through
a broker, in which case you may vote your shares at www.proxyvote.com.

Enter the control number listed on the proxy card you received in the mail and
follow the instructions on the web site.

BY TELEPHONE
[Telephone
photo]

Call toll-free 1.888.221.0697. Enter the control number listed on the proxy card
and follow the recorded instructions.

BY MAIL
[Mail Box
photo]

Complete and sign the proxy card and return it in the postage-paid envelope
provided in the shareholder mailing.

IN PERSON

The shareholder meeting will be held on March 15, 2007. Please notify AIM
Investments at 1.800.952.3502 if you plan to attend this meeting.

IF YOU HAVE ANY QUESTIONS...

If you have questions on the proxy statement or the voting process, please
contact your financial consultant or call AIM toll-free at 1.800.952.3502 any
business day between 7:30 a.m. and 7:00 p.m. CT.

If we have not received your proxy card after a reasonable amount of time, a
representative from our proxy solicitation firm, Computershare Fund Services,
may contact you to remind you to exercise your right to vote.


                Prospectuses | Help | Site Map | Terms of Use | Privacy

- --------------------------------------------------------------------------------

                      AIM INVESTMENT SERVICES, INC. 01/2007

       (Copyright) 2007 A I M Management Group Inc. All Rights Reserved.


AIM PROXY INFORMATION BY FUND

AIM ADVANTAGE HEALTH SCIENCES FUND

     1.  Please read the proxy statement in full. (PDF)

     2.  Access some typical questions that shareholders may have regarding the
         proxy statement. (PDF)

     3.  You may vote your shares at www.proxyweb.com unless your shares are
         held through a broker, in which case you may vote your shares at
         www.proxyvote.com.

ADDITIONAL FUND MATERIALS:

     -   Prospectus (PDF)

     -   Annual Report (PDF)

- --------------------------------------------------------------------------------

AIM OPPORTUNITIES I FUND

     1.  Please read the proxy statement in full. (PDF)

     2.  Access some typical questions that shareholders may have regarding the
         proxy statement. (PDF)

     3.  You may vote your shares at www.proxyweb.com unless your shares are
         held through a broker, in which case you may vote your shares at
         www.proxyvote.com.

ADDITIONAL FUND MATERIALS:

     -   Prospectus (PDF)

     -   Annual Report (PDF)

- --------------------------------------------------------------------------------

AIM OPPORTUNITIES II FUND

     1.  Please read the proxy statement in full. (PDF)

     2.  Access some typical questions that shareholders may have regarding the
         proxy statement. (PDF)

     3.  You may vote your shares at www.proxyweb.com unless your shares are
         held through a broker, in which case you may vote your shares at
         www.proxyvote.com.

ADDITIONAL FUND MATERIALS:

     -   Prospectus (PDF)

     -   Annual Report (PDF)

- --------------------------------------------------------------------------------





AIM OPPORTUNITIES III FUND

     1.  Please read the proxy statement in full. (PDF)

     2.  Access some typical questions that shareholders may have regarding the
         proxy statement. (PDF)

     3.  You may vote your shares at www.proxyweb.com unless your shares are
         held through a broker, in which case you may vote your shares at
         www.proxyvote.com.

ADDITIONAL FUND MATERIALS:

     -   Prospectus (PDF)

     -   Annual Report (PDF)

- --------------------------------------------------------------------------------

IF YOU HAVE ANY QUESTIONS...

If you have questions on the proxy statement or the voting process, please
contact your financial consultant or call AIM toll-free at 1.800.952.3502 any
business day between 7:30 a.m. and 7:00 p.m. CT.

If we have not received your proxy card after a reasonable amount of time, a
representative from our proxy solicitation
firm, Computershare Fund Services, may contact you to remind you to exercise
your right to vote.


             Prospectuses | Help | Site Map | Terms of Use | Privacy

- --------------------------------------------------------------------------------

                      AIM INVESTMENT SERVICES, INC. 01/2007

       (Copyright) 2007 A I M Management Group Inc. All Rights Reserved.


QUESTIONS & ANSWERS FOR:

                       AIM ADVANTAGE HEALTH SCIENCES FUND


We encourage you to read the proxy statement in full; however, the following
represent some typical questions that shareholders may have regarding the proxy
statement/prospectus.

HOW DO I VOTE?
Voting may take place in the following ways:

     o   You may vote your shares at www.proxyweb.com unless your shares are
         held through a broker, in which case you may vote your shares at
         www.proxyvote.com. You will need the control number from your proxy
         card to vote on the Internet. Because Internet voting is the most
         economical way to vote your proxy, we encourage all shareholders to use
         this method.
     o   You may call in your vote to a 24-hour automated system at
         1-888-221-0697. You will need the control number from your proxy card
         to vote by telephone. For questions or to vote through a customer
         service representative you may call 1-866-905-8141; you will be asked
         to verify your identity by providing certain information such as your
         current address and ZIP code.
     o   You may indicate your vote on the proxy card and return it in the
         postage-paid envelope provided in the shareholder mailing.
     o   If you do attend the meeting, you may vote your shares in person.
         Please notify AIM Investments by calling 1-800-952-3502 if you plan to
         attend the meeting.

HOW DOES THE BOARD RECOMMEND THAT I VOTE?
The Board recommends that you vote FOR the proposal on the proxy card.

WHY SHOULD I VOTE?
Every vote is important. If shareholders fail to vote their proxies, the fund
may not receive enough votes to go forward with the March 15, 2007, shareholder
meeting. If this happens, additional solicitations may have to be made to obtain
a quorum, or proxies may have to be resent to shareholders, which will result in
additional expense to the fund.

WHO HAS AIM CONTRACTED FOR THE SERVICES OF A PROXY SOLICITOR?
AIM has hired Computershare Fund Services as its proxy solicitor. If we do not
receive your vote after a reasonable amount of time, you may receive a telephone
call from them reminding you to vote your shares.

WILL MY VOTE BE CONFIDENTIAL USING THE ONLINE PROXY VOTING SYSTEM?
The Web proxy voting system offered by proxyweb.com maintains a high level of
security to ensure the confidentiality of your vote. Security features include:

     o   SECURE SOCKETS LAYER (SSL) - A security measure that encrypts all
         information that travels between proxyweb.com's Web server and the
         shareholder's computer.
     o   CONTROL NUMBER - Each shareholder is required to enter his or her
         control number. Proxyweb.com verifies the number and presents the
         holder with the proxy card.
     o   FIREWALL - To protect the confidentiality of your account records,
         proxyweb.com uses only control numbers and card codes to register
         votes. Voted positions are then periodically uploaded to our master
         database of shareholders listed as of the record date. All
         account-specific data remains behind our firewall.

HOW DO I SIGN THE PROXY CARD?
The following general rules for signing proxy cards may be of assistance to you
and could help avoid the time and expense involved in validating your vote if
you fail to sign your proxy card properly.

Individual Accounts: Shareholders should sign exactly as their name appears in
the account registration shown on the proxy card.

Joint Accounts: All joint owners should sign exactly as their names appear in
the account registration shown on the proxy card.

All Other Accounts: The capacity of the individual signing the proxy card (for
example, "trustee") should be indicated unless it is reflected in the form of
registration. If a corporation, limited liability company, or partnership,
please sign full entity name and indicate the signer's position with the entity.

WHAT IS THE DEADLINE FOR VOTING?
All votes must be received before or at the Shareholder Meeting, which will be
held on March 15, 2007 at 3:00 p.m. Central Time.

WHAT ARE THE PROPOSALS BEING PRESENTED AT THE MEETING AND WHAT AM I BEING ASKED
TO VOTE ON?

     o   You are being asked to vote on the approval of an Agreement and Plan of
         Reorganization (the "Agreement") under which all of the assets and
         liabilities of AIM Advantage Health Sciences Fund (the "Fund"), a
         portfolio of AIM Counselor Series Trust ("Trust"), will be transferred
         to AIM Global Health Care Fund ("Buying Fund"), a portfolio of AIM
         Investment Funds ("Buyer"), and Buyer will issue shares of each class
         of Buying Fund to shareholders of the corresponding class of shares of
         the Fund.

WHERE CAN I FIND MORE INFORMATION CONCERNING THE PROPOSAL?
Further details about the proposals can be found in the proxy statement.

Proxy: AIM Advantage Health Sciences Fund                            Page 1 of 1


          [AIM INVESTMENTS LOGO APPEARS HERE]--Registered Trademark--


                          INTERNET PROXY VOTING SERVICE
                                PROXY VOTING FORM
                       AIM ADVANTAGE HEALTH SCIENCES FUND

      THIS PROXY IS SOLICITED ON BEHALF OF THE BOARD. THE BOARD RECOMMENDS
                           VOTING "FOR" THE PROPOSAL.


                                                                                                      
Proposal 1.  Approve an Agreement and Plan of Reorganization (the "Agreement")        O FOR       O AGAINST       O ABSTAIN
             under which all of the assets and liabilities of AIM Advantage
             Health Sciences Fund (the "Fund"), a portfolio of AIM Counselor
             Series Trust ("Trust"), will be transferred to AIM Global Health
             Care Fund ("Buying Fund"), an investment portfolio of AIM
             Investment Funds ("Buyer"), and Buyer will issue shares of each
             class of Buying Fund to shareholders of the corresponding class of
             shares of the Fund.



- --------------------------------------------------------------------------------
        Please refer to the proxy statement for discussion of the matter.
 If no specification is made on the proposal, the proposal will be voted "For".
- --------------------------------------------------------------------------------


  To receive an optional email confirmation, enter your email address here:

              Please review your selection carefully before voting.
   If you vote more than once on the same Proxy, only your last (most recent)
                         vote will be considered valid.

                                       ------
                  Press this button to SUBMIT your Proxy Vote.
                                       ------


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                    Terms and Conditions. Privacy Statement.



                                   IVR TESTING

Welcome

Please enter the control number labeled as such or located in the box indicated
by an arrow on the upper portion of your proxy card.

To vote as the board recommends press 1 now. To vote otherwise press 0 now.

      PRESS 1:    You have voted as the board recommended. If this is correct
                  press 1.

                     If incorrect press 0.

                     Press 1: If you have received more then one proxy card you
                     must vote each card separately.

                     If you would like to vote another proxy press 1 now.

                     To end this call press 0 now.

                     Press 1: Please enter the control number labeled as such or
                     located in the box indicated by an arrow on the upper
                     portion of your proxy card.

                     Press 0: Thank you for voting.

                  To vote as the board recommends press 1 now.

                  To vote otherwise press 0 now.

         Press 1: You have voted as the board recommended. If this is correct
                  press 1 if incorrect press 0.

                     Press 1: If you have received more then 1 proxy card you
                              must vote each card separately. If you would like
                              to vote another proxy press 1 now.

                     To end this call press 0 now.

      PRESS 0:    Proposal 1 to vote for press 1, to vote against press 9 to
                  abstain press 0.

                     Proposal 2: Your votes have been cast as follows Proposal 1
                     For.

                     If this is correct press 1, if incorrect press 0.

Press 1 if you have received more than 1 proxy card you must vote each card
separately. If you would like to vote another proxy, press 1 now. (starts over
and repeats in its entirety.

      To end this call press 0 now.

      Press 0:  Thank you for voting.