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SUPPLEMENT TO THE PROSPECTUS OF
DEAN WITTER SELECT DIMENSIONS INVESTMENT SERIES
DATED MAY 1, 1997
CORE EQUITY PORTFOLIO
In October 1997 the Core Equity Portfolio's current sub-adviser, TCW Funds
Management, Inc. ("TCW"), indicated its intention to resign as sub-adviser to
the Core Equity Portfolio.
On November 6, 1997, the Board of Trustees unanimously recommended that a new
sub-advisory agreement between Dean Witter InterCapital ("InterCapital") and
Morgan Stanley Asset Management Inc. ("MSAM") be submitted to shareholders of
the Core Equity Portfolio for approval at a special meeting expected to be held
in February 1998. Under the proposed new sub-advisory agreement, InterCapital
would pay MSAM a fee equal, on an annual basis, to 40% of the management fee
receivable by InterCapital under its investment management agreement with Dean
Witter Select Dimensions Investment Series (the "Fund") on behalf of the Core
Equity Portfolio. This percentage is identical to the percentage payable to TCW
under the present sub-advisory agreement for the Core Equity Portfolio.
In addition, effective upon implementation of a new sub-advisory agreement, the
present investment management agreement between the Fund and InterCapital on
behalf of the Core Equity Portfolio would be amended to lower the management fee
payable by the Core Equity Portfolio under the investment management agreement
from the annual rate of 0.85% of the Core Equity Portfolio's average daily net
assets to 0.80% of the Core Equity Portfolio's average daily net assets.
Also, if the proposed sub-advisory agreement is approved by the shareholders of
the Core Equity Portfolio, the name of the Portfolio will be changed to the
Growth Portfolio.
BALANCED PORTFOLIO
Dean Witter InterCapital Inc. ("InterCapital") is the investment manager for the
Portfolio. TCW Funds Management, Inc. ("TCW") serves as sub-adviser to the
Balanced Portfolio pursuant to a sub-advisory agreement with InterCapital. In
October 1997, TCW indicated its intention to resign as sub-adviser to the
Balanced Portfolio.
On November 6, 1997, the Board of Trustees unanimously approved InterCapital's
proposal to assume the duties previously performed by TCW and to reduce the rate
of compensation payable to InterCapital under the investment management
agreement between InterCapital and the Fund on behalf of the Balanced Portfolio
from 0.75% of average daily net assets of the Balanced Portfolio to 0.60% of
average daily net assets of the Balanced Portfolio.
At the November 6th meeting, the Board also recommended that shareholders
approve a change in the investment objective of the Balanced Portfolio from high
total return through a combination of income and capital appreciation to an
investment objective of capital growth with reasonable income. The proposed
change in investment objective will be submitted to shareholders of the Balanced
Portfolio for approval at a special meeting expected to be held in February
1998.
Following approval by shareholders of the Balanced Portfolio of the proposed
change in investment objective, the name of the Balanced Portfolio will be
changed to Balanced Growth Portfolio and InterCapital will assume the duties
previously performed by TCW with respect to the Portfolio.
November 6, 1997
