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Filed Pursuant to Rule 497
Registration File No.: 33-46049
SUPPLEMENT TO THE PROSPECTUS OF
TCW/DW NORTH AMERICAN GOVERNMENT INCOME TRUST DATED FEBRUARY 5, 1997
On July 28, 1997, certain other open-end investment companies
("Multi-Class Funds") to which Dean Witter Services Company Inc. serves as
manager and TCW Funds Management, Inc. serves as adviser began offering their
shares in four classes (each, a "Class"), each with a different combination
of sales charges, ongoing fees and other features. TCW/DW North American
Government Income Trust (the "Fund") will continue to offer one class of
shares. In order to reflect implementation of this multiple class
distribution system, the Prospectus of the Fund is revised as follows:
In the section "Shareholder Services--Exchange Privilege," the term "CDSC
Funds" is amended to mean Class B shares of the Multi-Class Funds and, for
purposes of calculating the holding period and the applicable contingent
deferred sales charge ("CDSC") rate, shall also include shares of any Class
of a Multi-Class Fund that are subject to a CDSC.
In addition, shares of Class A, Class C and Class D of the Multi-Class
Funds may be exchanged for shares of the Fund. Such exchanges would be
effected on the same net asset value basis as exchanges from CDSC funds to
the Funds. Shares of the Fund received in an exchange for shares of Class C
or Class D of a Multi-Class Fund may be redeemed and exchanged only for
shares of the corresponding Class of a Multi-Class Fund or for shares of Dean
Witter Liquid Asset Fund Inc., Dean Witter U.S. Government Money Market
Trust, Dean Witter Tax-Free Daily Income Trust, Dean Witter California
Tax-Free Daily Income Trust or Dean Witter New York Municipal Money Market
Trust.
July 28, 1997
