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                                                                    EXHIBIT 5.01


                          [SIDLEY & AUSTIN LETTERHEAD]



                                October 22, 1999


ProFutures, Inc.
  as general partner of
  ProFutures Long/Short Growth Fund, L.P.
11612 Bee Cave Road
Suite 100
Austin, Texas 78733

                  RE:      PROFUTURES LONG/SHORT GROWTH FUND, L.P.
                           $75,218,153 OF UNITS OF
                           LIMITED PARTNERSHIP INTEREST (THE "UNITS")

Dear Sir or Madam:

                  We refer to the Registration Statement on Form S-1 (Reg. No.
333-______) filed by ProFutures Long/Short Growth Fund, L.P., (the "Registration
Statement"), a Delaware limited partnership (the "Partnership"), on or about
October 22, 1998 with the Securities and Exchange Commission under the
Securities Act of 1933, as amended (the "Securities Act"), relating to the
registration of $75,218,153 of Units of the Partnership. Capitalized terms not
defined herein have the meanings specified in the Registration Statement.

                  We are familiar with the proceedings to date with respect to
the proposed issuance and sale of the Units pursuant to the Prospectus and have
examined such records, documents and questions of law, and satisfied ourselves
as to such matters of fact, as we have considered relevant and necessary as a
basis for this opinion.

                  For purposes of rendering this opinion, we have assumed the
genuineness of all signatures, the legal capacity of natural persons, the
authenticity of all documents submitted to us as originals, the conformity to
originals of all documents submitted to us as certified or photostatic copies,
and the authenticity of the originals of such copies.

                  Based on the foregoing, we are of the opinion that:

                  1. The Partnership has been duly formed and is validly
existing in good standing as a limited partnership under the Delaware Revised
Uniform Limited Partnership Act (the "Act").

                  2. The General Partner has taken all corporate action required
to be taken by it to authorize the issuance and sale of the Units to prospective
investors and to authorize the admission to the Partnership of the persons
purchasing Units as Limited Partners of the Partnership.

                  3. Assuming (i) the due authorization, execution and delivery
to the General Partner of a Subscription Agreement and Power of Attorney (the
"Subscription Agreement") by each subscriber for Units (the "Subscribers"), (ii)
the due acceptance by the General Partner of each Subscription Agreement and the
due acceptance by the General Partner of the admission of each of the
Subscribers as a Limited Partner of the Partnership, (iii) the payment by each
Subscriber to the Partnership of the full consideration due for the Units to
which such Subscriber has subscribed, (iv) that the books and records of the
Partnership set forth all information required by the Limited Partnership
Agreement and the Act, including


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ProFutures, Inc.
October 22, 1999
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all information with respect to all persons and entities to be admitted as
Limited Partners and their contributions to the Partnership, (v) that the
Subscribers, as Limited Partners of the Partnership, do not participate in the
control of the business of the Partnership within the meaning of the Act, (vi)
that the Units are offered and sold as described in the Prospectus and the
Limited Partnership Agreement and (vii) that the representations and warranties
of the Subscribers in their respective Subscription Agreements are true and
correct, the Units to be issued to the Subscribers will represent valid and
legally issued limited partner interests in the Partnership and, subject to the
qualifications set forth below, will be fully paid and nonassessable limited
partner interests in the Partnership, as to which the Subscribers, as limited
partners of the Partnership, will have no liability in excess of their
obligations to make contributions to the Partnership, their obligations to make
other payments provided for in the Limited Partnership Agreement and their share
of the Partnership's assets and undistributed profits (subject to the obligation
of a Limited Partner to repay funds distributed to such Limited Partners by the
Partnership in certain circumstances).

                  4. There are no provisions in the Limited Partnership
Agreement the inclusion of which, subject to the terms and conditions set forth
therein, would cause the Limited Partners, as limited partners of the
Partnership, to be deemed to be participating in the control of the business of
the Partnership within the meaning of the Act.

                  This opinion is limited to the Act and the General Corporation
Law of the State of Delaware. We express no opinion as to the application of the
securities or blue sky laws of the various states (including the State of
Delaware) to the sale of the Units.

                  We hereby consent to the filing of this opinion as an Exhibit
to the Registration Statement and to all references to our firm included in or
made a part of the Registration Statement.

                                         Very truly yours,



                                         /s/  SIDLEY & AUSTIN