Exhibit 3.03
                           CERTIFICATE OF AMENDMENT
                                      OF
                     RESTATED CERTIFICATE OF INCORPORATION
                                      OF
                        CSG SYSTEMS INTERNATIONAL, INC.
                        -------------------------------


     CSG Systems International, Inc. (the "Corporation"), a corporation
organized and existing under the laws of the State of Delaware, hereby certifies
as follows:

     1.   The name of the corporation is CSG Systems International, Inc.

     2.   The Board of Directors of the Corporation duly adopted a resolution
proposing that the Restated Certificate of Incorporation of the Corporation be
amended by adding thereto a new Article VII reading as follows and declaring the
advisability of such proposed amendment:

                                 "ARTICLE VII

             A. The business and affairs of the Corporation shall be 
          managed by or under the direction of a Board of Directors.  
          The Board of Directors shall consist of not fewer than five 
          (5) members and not more than thirteen (13) members, the exact 
          number of authorized directors within such range to be fixed 
          from time to time by a resolution of the Board of Directors 
          adopted by the affirmative vote of at least a majority of the 
          total number of authorized directors most recently fixed by the 
          Board of Directors.  The directors of the Corporation shall be 
          divided into three classes for the purpose of determining their 
          terms of office.  Each such class shall consist, as nearly as 
          possible, of one-third of the total number of directors fixed 
          by the Board of Directors.  At the annual meeting of stock-
          holders of the Corporation held in 1997, one class of directors
          (designated as Class I) shall be elected for a term expiring at 
          the annual meeting of stockholders of the Corporation held in 
          1998, one class of directors (designated as Class II) shall be 
          elected for a term expiring at the annual meeting of stock-
          holders of the Corporation held in 1999, and one class of 
          directors (designated as Class III) shall be elected for a term 
          expiring at the annual meeting of stockholders of the 
          Corporation held in 2000.  At each succeeding annual meeting of 
          stockholders of the Corporation, beginning in 1998, successors 
          to the class of directors whose term expires at that annual
          meeting shall be elected for a term expiring at the annual 
          meeting of stockholders of the Corporation held in the third 
          year following the year of their 

 
          election.  If the number of directors is changed, then
          any increase or decrease in such number shall be appor-
          tioned by the Board of Directors among the classes of 
          directors so as to maintain as nearly as possible an equal 
          number of directors in each class.  No reduction in the 
          authorized number of members of the Board of Directors 
          shall have the effect of removing any director from office
          before that director's term of office expires.  Vacancies 
          on the Board of Directors and newly created directorships 
          resulting from an increase in the authorized number of 
          members of the Board of Directors may be filled only by a 
          majority of the directors then in office, although less 
          than a quorum, or by a sole remaining director.  Each
          director, including a director elected to fill a vacancy 
          or a newly created directorship, shall hold office until 
          the next election of the class of directors to which such 
          director belongs and until his or her successor is elected 
          and qualified or until his or her earlier death, resignation, 
          or removal from office for cause.  Any director or the entire 
          Board of Directors may be removed from office at any time but
          only for cause and only by the affirmative vote of the holders 
          of at least seventy-five percent (75%) of the voting power of 
          all outstanding shares of capital stock of the Corporation 
          then entitled to vote in an election of directors of the 
          Corporation, voting as a single class.

             B. Nominations of persons for election to the Board of 
          Directors may be made at a meeting of stockholders of the 
          Corporation either by or at the direction of the Board of 
          Directors or by any stockholder of record entitled to vote 
          in the election of directors at such meeting who has complied 
          with the notice procedures set forth in this Paragraph B.  
          A stockholder who desires to nominate a person for election 
          to the Board of Directors at a meeting of stockholders of the
          Corporation and who is eligible to make such nomination must 
          give timely written notice of the proposed nomination to the 
          secretary of the Corporation.  To be timely, a stockholder's 
          notice given pursuant to this Paragraph B must be received at 
          the principal executive office of the Corporation not less 
          than one hundred twenty (120) calendar days in advance of the 
          date which is one year later than the date of the proxy 
          statement of the Corporation released to stockholders in
          connection with the previous year's annual meeting of stock-
          holders of the Corporation; provided, however, that if no 
          annual meeting of stockholders of the Corporation was held in 
          the previous year or if the date of the forthcoming annual 
          meeting of stockholders has been changed by more than thirty 
          (30) calendar days from the date 

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          contemplated at the time of the previous year's proxy 
          statement or if the forthcoming meeting is not an annual 
          meeting of stockholders of the Corporation, then to be timely 
          such stockholder's notice must be so received not later than 
          the close of business on the tenth day following the earlier 
          of (a) the day on which notice of the date of the forthcoming 
          meeting was mailed or given to stockholders by or on behalf 
          of the Corporation or (b) the day on which public disclosure of
          the date of the forthcoming meeting was made by or on behalf of 
          the Corporation.  Such stockholder's notice to the secretary of 
          the Corporation shall set forth (a) as to each person whom the 
          stockholder proposes to nominate for election or re-election as 
          a director (i) the name, age, business address, and residence 
          address of such person, (ii) the principal occupation or employ-
          ment of such person, (iii) the class and number of shares of 
          capital stock of the Corporation which then are beneficially 
          owned by such person, (iv) any other information relating to 
          such person that is required by law or regulation to be 
          disclosed in solicitations of proxies for the election of 
          directors of the Corporation, and (v) such person's written 
          consent to being named as a nominee for election as a director 
          and to serve as a director if elected and (b) as to the stock-
          holder giving the notice (i) the name and address, as they 
          appear in the stock records of the Corporation, of such stock-
          holder, (ii) the class and number of shares of capital stock of 
          the Corporation which then are beneficially owned by such
          stockholder, (iii) a description of all arrangements or under-
          standings between such stockholder and each nominee for 
          election as a director and any other person or persons (naming 
          such person or persons) relating to the nomination proposed to 
          be made by such stockholder, and (iv) any other information 
          required by law or regulation to be provided by a stockholder 
          intending to nominate a person for election as a director of 
          the Corporation.  At the request of the Board of Directors, 
          any person nominated by or at the direction of the Board of
          Directors for election as a director of the Corporation shall 
          furnish to the secretary of the Corporation the information 
          concerning such nominee which is required to be set forth in 
          a stockholder's notice of a proposed nomination.  No person 
          shall be eligible for election as a director of the Corpor-
          ation unless nominated in compliance with the procedures set 
          forth in this Paragraph B.  The chairman of a meeting of 
          stockholders of the Corporation shall refuse to accept the
          nomination of any person not made in compliance with the 
          procedures set forth in this Paragraph B, and such defective 
          nomination shall be disregarded.

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             C. Notwithstanding any provision of this Certificate of
          Incorporation or the by-laws of the Corporation to the 
          contrary, the affirmative vote of the holders of at least 
          seventy-five percent (75%) of the voting power of all out-
          standing shares of capital stock of the Corporation then 
          entitled to vote in an election of directors of the Corpor-
          ation, voting as a single class, shall be required to alter,
          amend, or repeal this Article VII or to adopt any provision 
          of this Certificate of Incorporation or the by-laws of the 
          Corporation which is inconsistent with this Article VII."

     3.   Such amendments have been duly adopted in accordance with the
applicable provisions of Section 242 of the General Corporation Law of the State
of Delaware.

     IN WITNESS WHEREOF, the Corporation has caused this Certificate to be
signed by the Chairman of the Board and Chief Executive Officer of the
Corporation this 29th day of May, 1997.

                                CSG SYSTEMS INTERNATIONAL, INC.,
                                a Delaware corporation

                                By: /s/ Neal C. Hansen
                                    ------------------------------
                                   Neal C. Hansen, Chairman of the
                                   Board and Chief Executive Officer

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