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                                                                       EXHIBIT 5


            [FRESHMAN, MARANTZ, ORLANSKI, COOPER & KLEIN LETTERHEAD]


                                 June 30, 1999

Mustang Software, Inc.
6200 Lake Ming Road
Bakersfield CA 93306

                  Re:      Mustang Software, Inc.
                           Registration Statement on Form S-3
                           SEC 333-78687

Dear Sirs:

We have acted as special counsel to Mustang Software, Inc., a California
corporation (the "Company"), in connection with the preparation and filing with
the Securities and Exchange Commission of the Registration Statement on Form
S-3, File No. 333-78687, together with Amendment No.1 thereto (collectively, the
"Registration Statement"), of the Company, with exhibits as filed in connection
therewith and the form of prospectus contained therein, for registration for
resale under the Securities Act of 1933, as amended, of 637,634 shares of the
Company's common stock, no par value (the Common Stock ).

For purposes of this opinion, we have examined such matters of law and
originals, or copies certified or otherwise identified to our satisfaction, of
such documents, corporate records and other instruments as we have deemed
necessary. In our examination, we have assumed the genuineness of all
signatures, the authenticity of all documents submitted to us as originals, the
conformity to original documents of all documents submitted to us as certified,
photostatic or conformed copies, and the authenticity of the originals of all
such latter documents. We have also assumed the due execution and delivery of
all documents where due execution and delivery are prerequisites to the
effectiveness thereof. We have relied upon certificates of public officials and
certificates of officers of the Company for the accuracy of material, factual
matters contained therein that were not independently established.

Based on the foregoing and on all other instruments, documents and matters
examined for the rendering of this opinion, it is our opinion that

         1.    in the case of the shares of Common Stock that are outstanding at
the date hereof and registered pursuant to the Registration Statement, such
shares are legally issued, fully paid and non-assessable shares of the Common
Stock of the Company;


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Mustang Software, Inc.
June 30, 1999
Page 2


         2.    in the case of the shares of Common Stock registered pursuant to
the Registration Statement issuable upon conversion of the Series A Convertible
Preferred Stock of the Company, such shares will be, upon conversion of such
Series A Convertible Preferred Stock in accordance with the terms applicable to
such the Series A Convertible Preferred Stock, legally issued, fully paid and
non-assessable shares of the Common Stock; and

         3.    in the case of the shares of Common Stock registered pursuant to
the Registration Statement issuable upon exercise of the warrants, such shares
will be, upon exercise of the warrants and payment of the applicable exercise
price therefor, legally issued, fully paid and non-assessable shares of the
Common Stock.

We express no opinion as to the applicability or effect of any laws, orders or
judgments of any state or jurisdiction other than the substantive laws of the
State of California. Further, our opinion is based solely upon existing laws,
rules and regulations, and we undertake no obligation to advise you of any
changes that may be brought to our attention after the date hereof.

We consent to the use of our name under the caption "Legal Matters" in the
Prospectus, constituting part of the Registration Statement, and to the filing
of this opinion as an exhibit to the Registration Statement.

By giving you this opinion and consent, we do not admit that we are experts with
respect to any part of the Registration Statement or Prospectus within the
meaning of the term expert as used in Section 11 of the Securities Act, or the
rules and regulations promulgated thereunder by the SEC, nor do we admit that we
are in the category of persons whose consent is required under Section 7 of the
Securities Act.

                                                Very truly yours,


                                                /s/ FRESHMAN, MARANTZ, ORLANSKI,
                                                    COOPER & KLEIN
                                                --------------------------------
                                                    FRESHMAN, MARANTZ, ORLANSKI,
                                                    COOPER & KLEIN