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                      SALOMON BROTHERS INVESTMENT SERIES
 
                             7 WORLD TRADE CENTER
                           NEW YORK, NEW YORK 10048
                                (888) 777-0102
 
                       SUPPLEMENT DATED MARCH 9, 1998 TO
                        PROSPECTUS DATED APRIL 29, 1997
 
  The following information replaces the section entitled "Certain Qualified
Purchasers" on page 96 of the current Prospectus for Salomon Brothers
Investment Series:
 
    CERTAIN QUALIFIED PURCHASERS. No front end sales charge is applicable to
  any sale of Class A shares to a Director or officer of a Fund and to their
  immediate families (i.e., the spouse, children, mother or father of such
  persons), employees of SBAM and their immediate families, or any full-time
  employee or registered representative of the Distributor or of broker-
  dealers having dealer agreements with the Distributor ("Selling Broker")
  and their immediate families (or any trust, pension, profit sharing or
  other benefit plan for the benefit of such persons), any full-time employee
  of a bank, savings and loan, credit union or other financial institution
  that utilizes a Selling Broker to clear purchases of the Funds' shares and
  their immediate families, participants in certain "wrap-fee" or asset
  allocation programs sponsored by broker-dealers and other financial
  institutions that have entered into agreements with Salomon Brothers, any
  accounts established on behalf of registered investment advisers or their
  clients by broker-dealers that charge a transaction fee and that have
  entered into agreements with Salomon Brothers.
 
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  The following information supplements and should be read in conjunction with
the caption "Investment Manager" under the heading of the current Prospectus
for Salomon Brothers Investment Series (the "Series") entitled "Management"
and the caption "Distributor" under the heading of such Prospectus entitled
"Purchase of Fund Shares."
 
  "On November 28, 1997, Salomon Inc ("Salomon"), the ultimate parent company
of Salomon Brothers Asset Management Inc ("SBAM"), Salomon Brothers Asset
Management Limited ("SBAM Ltd."), Salomon Brothers Asset Management Asia
Pacific Limited ("SBAM AP"), and Salomon Brothers Inc ("Salomon Brothers"),
the Series Funds' distributor, merged with and into Smith Barney Holdings
Inc., a subsidiary of Travelers Group Inc. ("Travelers"), to form a new
company called Salomon Smith Barney Holdings Inc. (the "Transaction"). Upon
consummation of the Transaction, Travelers became the ultimate parent of SBAM,
SBAM Ltd., SBAM AP and Salomon Brothers, which continue to serve as the
investment adviser, subadvisers and distributor, respectively, to the Series.
Travelers is a diversified financial services company engaged in investment
services, asset management, consumer finance and life and property casualty
insurance services.
 
  Under certain interpretations, the Transaction might be deemed to create an
"assignment," as defined in the Investment Company Act of 1940, as amended,
of: (i) the Management Contracts with SBAM; (ii) the Subadvisory Agreements
between SBAM and SBAM Ltd. on the one hand and SBAM and SBAM AP, on the other
hand, with regard to certain of the Funds; and (iii) the Distribution
Agreements with Salomon Brothers, which, if so interpreted, would have
resulted in the termination of such contracts and agreements. Accordingly, the
Board approved new management contracts, subadvisory agreements and
distribution agreements for the Funds identical in all material respects to
the existing contracts and agreements, which became effective on November 28,
1997. The new management and subadvisory agreements will be presented to
stockholders for approval at Special Meetings of Stockholders scheduled to be
held on January 14, 1998."