EXHIBIT 5.1


                                                                    May 12, 1999

Board of Directors of
Jones Apparel Group, Inc.
250 Rittenhouse Circle
Bristol, Pennsylvania 19007

Ladies and Gentlemen:

               I have acted as counsel for Jones Apparel Group, Inc., a
Pennsylvania corporation ("Jones"), in connection with the preparation of a
Registration Statement on Form S-4, Amendment No. 1 (such Registration Statement
as so amended being hereinafter referred to as the "Registration Statement") to
which is being filed on the date hereof by Jones with the Securities and
Exchange Commission under the Securities Act of 1933 (the "Act"). The
Registration Statement relates to the proposed issuance by Jones of up to
24,426,396 shares (the "Shares") of its common stock, par value $0.01 per share,
pursuant to the Agreement and Plan of Merger (the "Merger Agreement") dated as
of March 1, 1999 among Jones, Jill Acquisition Sub Inc., a Delaware corporation
that is a wholly owned subsidiary of Jones ("Merger Sub"), and Nine West Group
Inc., a Delaware corporation ("Nine West"). The Merger Agreement provides for
the merger (the "Merger") of Nine West with and into Merger Sub, with Merger Sub
surviving as a wholly owned subsidiary of Jones.

               In that connection, I have examined originals, or copies
certified or otherwise identified to my satisfaction, of such documents,
corporate records and other instruments as I have deemed necessary or
appropriate for the purposes of this opinion, including: (a) the Registration
Statement and (b) the proxy statement/prospectus that forms a part of the
Registration Statement. In such examination, I have assumed the genuineness of
all signatures and the authenticity of all documents submitted to me as copies.
In examining agreements executed by parties other than Jones and Merger Sub, I
have assumed that such parties had the power, corporate or other, to enter into
and perform all obligations thereunder and also have assumed the due
authorization by all requisite action, corporate or other, and execution and
delivery by such parties of such documents, and the validity and binding effect
thereof. As







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May 12, 1999
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to any facts material to the opinion expressed herein which I have not
independently verified or established, I have relied upon statements and
representations of officers and representatives of Jones and others.

               Based on such examination, I am of the opinion that the Shares
have been duly authorized for issuance and, when issued in accordance with the
terms and conditions of the Merger Agreement, will be validly issued, fully paid
and non-assessable.

               I am admitted to practice in the State of New York, and I express
no opinion as to any matters governed by any law other than the law of the State
of New York and the Federal law of the United States of America.

               In rendering this opinion, I have relied upon the opinion dated
May 12, 1999, of Mesirov Gelman Jaffe Cramer & Jamieson, LLP, a copy of which
appears as Exhibit 5.2 to the Registration Statement, as to all matters of law
covered therein relating to the laws of the Commonwealth of Pennsylvania and the
General Corporation Law of the State of Delaware.

               I hereby consent to the inclusion of this opinion as an exhibit
to the Registration Statement and to the reference to me under the heading
"Legal Matters" in the proxy statement/prospectus that forms a part of the
Registration Statement. In giving such consent, I do not hereby admit that I am
in the category of persons whose consent is required under Section 7 of the Act.

                                              Very truly yours,

                                              /s/ Ira M. Dansky
                                              ----------------------
                                              Ira M. Dansky
                                              General Counsel
                                              Jones Apparel Group, Inc.