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                                                                    EXHIBIT 5.01


                          [SIDLEY & AUSTIN LETTERHEAD]




                                December 22, 1998


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.
                           $60,000,000 OF UNITS OF
                           LIMITED PARTNERSHIP INTEREST (THE "UNITS")

Dear Sir or Madam:

                  We refer to the Registration Statement on Form S-1 (Reg. No.
333-63129) filed by ProFutures Long/Short Growth Fund, L.P., formerly ProFutures
Bull & Bear Fund, L.P., (the "Registration Statement"), a Delaware limited
partnership (the "Partnership"), on or about September 10, 1998 with the
Securities and Exchange Commission under the Securities Act of 1933, as amended
(the "Securities Act"), and Amendment No. 1 thereto filed with the Commission on
or about December 22, 1998 relating to the registration of $60,000,000 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


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ProFutures, Inc.
December 22, 1998
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records of the Partnership set forth all information required by the Limited
Partnership Agreement and the Act, including 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,



                                             SIDLEY & AUSTIN