Exhibit 5.1

                        [LETTERHEAD OF SIDLEY & AUSTIN]
 
                               December 4, 1996


MoneyGram Payment Systems, Inc.
7401 West Mansfield Avenue
Lakewood, Colorado  80235


Ladies and Gentlemen:

          We have acted as special counsel to MoneyGram Payment Systems, Inc., a
Delaware corporation (the "Company"), in connection with the registration of the
offer and sale of up to 16,625,000 shares of Common Stock, par value $.01 per
share, of the Company (the "Shares") by Integrated Payment Systems Inc., a
Delaware corporation (the "Selling Stockholder"), pursuant to a Registration
Statement on Form S-1 (Registration No. 333-228), as amended, filed with the
Securities and Exchange Commission (the "Commission") and to which this opinion
appears as Exhibit 5.1 (the "Registration Statement").

          We have examined originals or certified or photostatic copies of such
records of the Company, certificates of officers of the Company and public
officials and such other documents as we have deemed relevant or necessary as
the basis of the opinion set forth below.  In such examination, we have assumed
the authenticity of all documents submitted to us as originals, the genuineness
of all signatures, the legal capacity of all natural persons and the conformity
with the original documents of any copies thereof submitted to us for our
examination.  Based on the foregoing, we are of the following opinion:

          The Shares will be legally issued, fully paid and nonassessable when
          (i) the Company's Board of Directors shall have adopted final
          resolutions authorizing the issuance of 16,624,900 of the Shares to
          the Selling Stockholder pursuant to the Contribution Agreement among
          the Company, First Data Corporation and the Selling Stockholder (the
          "Contribution Agreement"), (ii) the transactions contemplated by the
          Contribution Agreement shall have been duly consummated and (iii)
          certificates representing the Shares shall have been duly executed,
          countersigned and registered and duly delivered to the Selling
          Stockholder against receipt of the consideration provided therefor in
          the Contribution Agreement.

 
MoneyGram Payment Systems, Inc.
December 4, 1996
Page 2
 
          We do not find it necessary for purposes of this opinion to cover, and
accordingly we express no opinion as to, the application of the securities or 
blue sky laws of the various states or the District of Columbia to the sale of 
the Shares.

          We hereby consent to the filing of this opinion as Exhibit 5 to the
Registration Statement and the reference to this Firm under the heading "Legal
Matters" in the Prospectus constituting part of the Registration Statement. In
giving such consent, we do not thereby admit that we are within the category of
persons from whom consent is required by Section 7 of the Securities Act of 
1933, as amended, or the related rules promulgated by the Commission.


                                    Very truly yours,

                                    /s/ Sidley & Austin