<PAGE>
AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON OCTOBER 31, 1997
REGISTRATION NO. 333-24109
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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
------------------------
POST-EFFECTIVE AMENDMENT NO. 1
TO THE
FORM S-1
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933
------------------------
DEAN WITTER PORTFOLIO STRATEGY FUND L.P.
(Exact name of registrant as specified in charter document)
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<S> <C> <C>
DELAWARE 6793 13-3589337
(State of (Primary Standard (I.R.S. Employer
Organization Industrial Identification
of Issuer) Classification Code Number) Number)
</TABLE>
------------------------
Two World Trade Center, 62nd Floor
New York, New York 10048
(212) 392-8899
(Address, including zip code, and telephone number, including
area code, of registrant's principal executive offices)
Mark J. Hawley
DEMETER MANAGEMENT CORPORATION
Two World Trade Center, 62nd Floor
New York, New York 10048
(212) 392-8899
(Name, address, including zip code, and telephone number,
including area code, of agent for service)
------------------------
COPIES OF COMMUNICATIONS TO:
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<S> <C>
Edwin L. Lyon, Esq. Michael T. Gregg, Esq.
Cadwalader, Wickersham & Taft Dean Witter Reynolds Inc.
1333 New Hampshire Avenue, N.W. Two World Trade Center, 62nd Floor
Washington, D.C. 20036 New York, New York 10048
(202) 862-2200 (212) 392-5530
</TABLE>
------------------------
If any of the securities being registered on this Form are to be offered on
a delayed or continuous basis pursuant to Rule 415 under the Securities Act of
1933 check the following box. / /
If this Form is filed to register additional securities for an offering
pursuant to Rule 462(b) under the Securities Act, please check the following box
and list the Securities Act registration statement number of the earlier
effective registration statement for the same offering. / /
If this Form is a post-effective amendment filed pursuant to Rule 462(c)
under the Securities Act, check the following box and list the Securities Act
registration statement number of the earlier effective registration statement
for the same offering. / /
If delivery of the prospectus is expected to be made pursuant to Rule 434,
please check the following box. / /
------------------------
THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR DATES
AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL FILE
A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION STATEMENT
SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(A) OF THE
SECURITIES ACT OF 1933 OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME
EFFECTIVE ON SUCH DATE AS THE COMMISSION, ACTING PURSUANT TO SAID SECTION 8(A),
MAY DETERMINE.
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<PAGE>
This Post-Effective Amendment No. 1 to the Registration Statement on Form
S-1 (Reg. No. 333-24109) (the "Registration Statement") of Dean Witter Portfolio
Strategy Fund L.P. (the "Registrant") consists of a cover page, this page, and a
signature page.
The Registrant offered 50,000 Units of Limited Partnership Interest
("Units") on a "best efforts" basis through a Prospectus dated May 12, 1997.
Units were issued and sold at a closing (the "Closing") that was held as of
August 1, 1997. At the Closing, the Registrant accepted $43,029,508.53 in
subscriptions for Units, and 18,764.225 Units were issued at a price of
$2,293.13, the "Net Asset Value" thereof as of the close of business on the last
day of the month immediately preceding the Closing.
Accordingly, pursuant to Item 512(a)(3) of Regulation S-K and undertaking
(4) in Item 17 of the Registration Statement, the Registrant hereby deregisters
the 31,235.775 Units that were not sold in the public offering and that remain
registered under the Registration Statement.
<PAGE>
SIGNATURES
Pursuant to the requirements of the Securities Act of 1933, the registrant
has duly caused this Post-Effective Amendment No. 1 to the Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of New York and State of New York on the 31st day of
October, 1997.
DEAN WITTER PORTFOLIO STRATEGY FUND L.P.
By: DEMETER MANAGEMENT
CORPORATION,
General Partner
By: /s/ MARK J. HAWLEY
-------------------------------------
Mark J. Hawley, President
Pursuant to the requirements of the Securities Act of 1933, this
Post-Effective Amendment No. 1 to the Registration Statement has been signed by
the following persons in the capacities and on the dates indicated.
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<CAPTION>
SIGNATURE TITLE DATE
- --------------------------------------- --------------------------------------------------- -------------------
<S> <C> <C>
DEMETER MANAGEMENT General Partner
CORPORATION
By: /s/ MARK J. HAWLEY President and Director of the General Partner October 31, 1997
------------------------------
Mark J. Hawley
/s/ RICHARD M. DEMARTINI Chairman of the Board and Director of the General October 31, 1997
------------------------------ Partner
Richard M. DeMartini
/s/ LAWRENCE VOLPE Director of the General Partner October 31, 1997
------------------------------
Lawrence Volpe
Director of the General Partner
------------------------------
Joseph G. Siniscalchi
Director of the General Partner
------------------------------
Edward C. Oelsner, III
/s/ ROBERT E. MURRAY Director of the General Partner October 31, 1997
------------------------------
Robert E. Murray
/s/ PATTI L. BEHNKE Vice President and Chief Financial October 31, 1997
------------------------------ and Principal Accounting Officer of the General
Patti L. Behnke Partner
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