AMENDMENT NO. 1 MASTER ADMINISTRATIVE SERVICES AGREEMENT

                                                               EXHIBIT h (2) (b)

                                 AMENDMENT NO. 1
                    MASTER ADMINISTRATIVE SERVICES AGREEMENT


         The Master Administrative Services Agreement (the "Agreement"), dated
June 1, 2000, by and between A I M Advisors, Inc., a Delaware corporation, and
Short-Term Investments Trust, a Delaware business trust, is hereby amended as
follows:

         Section 3 of the Agreement is hereby deleted in its entirety and
replaced with the following:

                  "3. As full compensation for the services performed and the
         facilities furnished by or at the direction of the Administrator, the
         Portfolios shall reimburse the Administrator for expenses incurred by
         them or their affiliates in accordance with the methodologies
         established from time to time by the Trust's Board of Trustees. Such
         amounts shall be paid to the Administrator on a monthly basis."

         All other terms and provisions of the Agreement not amended herein
shall remain in full force and effect.

Dated: May 9, 2001

                                            A I M ADVISORS, INC.


Attest: /s/ P. XXXXXXXX XXXXX               By: /s/ XXXXXX X. XXXXXX
       ---------------------------             ---------------------------------
       Assistant Secretary                     Xxxxxx X. Xxxxxx
                                               President


(SEAL)


                                            SHORT-TERM INVESTMENTS TRUST


Attest: /s/ XXXXX X. XXXXXXX                By: /s/ XXXXXX X. XXXXXX
       ---------------------------             ---------------------------------
       Assistant Secretary                     Xxxxxx X. Xxxxxx
                                               President


(SEAL)