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SHORT-TERM INVESTMENTS TRUST
TREASURY PORTFOLIO
INSTITUTIONAL CLASS
Supplement dated July 1, 1998
to the Prospectus dated December 17, 1997.
The "Borrowing Money/Reverse Repurchase Agreements" section on page 7 is hereby
deleted in its entirety and replaced with the following:
"BORROWING MONEY/REVERSE REPURCHASE AGREEMENTS. The Portfolio may borrow
money and enter into reverse repurchase agreements with respect to its
portfolio securities in amounts up to 10% of the value of its total
assets at the time of borrowing or entering into a reverse repurchase
agreement. Reverse repurchase agreements involve the sale by the
Portfolio of a portfolio security at an agreed-upon price, date and
interest payment. The Portfolio will borrow money or enter into reverse
repurchase agreements solely for temporary or defensive purposes, such
as to facilitate the orderly sale of portfolio securities or to
accommodate abnormally heavy redemption requests should they occur.
Reverse repurchase transactions are limited to a term not to exceed 92
days. The Portfolio will use reverse repurchase agreements when the
interest income to be earned from the securities that would otherwise
have to be liquidated to meet redemption requests is greater than the
interest expense of the reverse repurchase transaction. The Portfolio
will give shareholders notice of its intent to enter into a reverse
repurchase agreement in sufficient time to permit shareholder
redemptions before the Portfolio enters into any reverse repurchase
agreements. Reverse repurchase agreements involve the risk that the
market value of securities retained by the Portfolio in lieu of
liquidation may decline below the repurchase price of the securities
sold by the Portfolio which it is obligated to repurchase. The risk, if
encountered, could cause a reduction in the net asset value of the
Portfolio's shares. Reverse repurchase agreements are considered to be
borrowings by the Portfolio under the 1940 Act."
