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                       SECURITIES AND EXCHANGE COMMISSION
                              Washington, DC 20549



                                  SCHEDULE 13G
                              (Section 240.13d-102)

             INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
        TO SECTIONS 240.13d-1(b), (c) and(d) AND AMENDMENTS THERETO FILED
                          PURSUANT TO SECTION 240.13d-2
                          (Amendment No. ___________)1



                         CSG Systems International, Inc.
--------------------------------------------------------------------------------
                                (Name of Issuer)


                     Common Stock, Par Value $0.01 Per Share
--------------------------------------------------------------------------------
                         (Title of Class of Securities)


                                    126349109
--------------------------------------------------------------------------------
                                 (CUSIP Number)


                                March 31, 2003
--------------------------------------------------------------------------------
             (Date of Event which Requires Filing of this Statement)


         Check the appropriate box to designate the rule pursuant to which this
Schedule is filed:

                  | |      Rule 13d-1(b)
                  |X|      Rule 13d-1(c)
                  | |      Rule 13d-1(d)

--------
     1 The  remainder  of this cover  page  shall be filled out for a  reporting
person's  initial  filing on this  form with  respect  to the  subject  class of
securities,  and for any subsequent amendment containing information which would
alter the disclosures provided in a prior cover page.
     The  information  required in the remainder of this cover page shall not be
deemed to be "filed"  for the purpose of Section 18 of the  Securities  Exchange
Act of 1934 ("Act") or otherwise  subject to the  liabilities of that section of
the Act but shall be subject to all other  provisions of the Act  (however,  see
the Notes).


                               Page 1 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Farallon Capital Partners, L.P.
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  is a  beneficial  owner  only  of  the  securities
                    reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            California
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     555,900
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     555,900
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            555,900
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            1.1 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            PN
------------====================================================================


                               Page 2 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Farallon Capital Institutional Partners, L.P.
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  is a  beneficial  owner  only  of  the  securities
                    reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            California
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     532,700
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     532,700
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            532,700
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            1.0 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            PN
------------====================================================================


                               Page 3 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Farallon Capital Institutional Partners II, L.P.
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  is a  beneficial  owner  only  of  the  securities
                    reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            California
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     47,000
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     47,000
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            47,000
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            0.1 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            PN
------------====================================================================

                               Page 4 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Farallon Capital Institutional Partners III, L.P.
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  is a  beneficial  owner  only  of  the  securities
                    reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            Delaware
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

        SHARES                       -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     48,500
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     48,500
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            48,500
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            0.1 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            PN
------------====================================================================

                               Page 5 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Tinicum Partners, L.P.
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  is a  beneficial  owner  only  of  the  securities
                    reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            New York
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     30,800
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     30,800
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            30,800
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            0.1 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            PN
------------====================================================================


                               Page 6 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Farallon Capital Management, L.L.C.
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  may be  deemed  a  beneficial  owner  only  of the
                    securities reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            Delaware
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     1,885,194
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     1,885,194
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            1,885,194
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            3.6 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            IA, OO
------------====================================================================

                               Page 7 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Farallon Partners, L.L.C.
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  may be  deemed  a  beneficial  owner  only  of the
                    securities reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            Delaware
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     1,214,900
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     1,214,900
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            1,214,900
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            2.3 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            OO
------------====================================================================


                               Page 8 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            David I. Cohen
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  may be  deemed  a  beneficial  owner  only  of the
                    securities reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            United States
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     3,100,094
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     3,100,094
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            3,100,094
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            5.9 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            IN
------------====================================================================


                               Page 9 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Joseph F. Downes
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  may be  deemed  a  beneficial  owner  only  of the
                    securities reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            United States
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     3,100,094
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     3,100,094
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            3,100,094
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            5.9 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            IN
------------====================================================================


                              Page 10 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            William F. Duhamel
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  may be  deemed  a  beneficial  owner  only  of the
                    securities reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            United States
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     3,100,094
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     3,100,094
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            3,100,094
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            5.9 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            IN
------------====================================================================


                              Page 11 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Richard B. Fried
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  may be  deemed  a  beneficial  owner  only  of the
                    securities reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            United States
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     3,100,094
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     3,100,094
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            3,100,094
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            5.9 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            IN
------------====================================================================


                              Page 12 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Monica R. Landry
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  may be  deemed  a  beneficial  owner  only  of the
                    securities reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            United States
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     3,100,094
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     3,100,094
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            3,100,094
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            5.9 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            IN
------------====================================================================


                              Page 13 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            William F. Mellin
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  may be  deemed  a  beneficial  owner  only  of the
                    securities reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            United States
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     3,100,094
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     3,100,094
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            3,100,094
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            5.9 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            IN
------------====================================================================

                              Page 14 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Stephen L. Millham
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  may be  deemed  a  beneficial  owner  only  of the
                    securities reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            United States
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     3,100,094
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     3,100,094
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            3,100,094
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            5.9 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            IN
------------====================================================================


                              Page 15 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Thomas F. Steyer
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  may be  deemed  a  beneficial  owner  only  of the
                    securities reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            United States
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     3,100,094
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     3,100,094
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            3,100,094
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            5.9 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            IN
------------====================================================================

                              Page 16 of 22 Pages




                                       13G
===================
CUSIP No. 126349109
===================

------------====================================================================
    1       NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Mark C. Wehrly
------------====================================================================
    2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

                                                             (a) [   ]

                                                             (b) [ X ]**

               **   The reporting  persons  making this filing hold an aggregate
                    of  3,100,094  Shares,   which  is  5.9%  of  the  class  of
                    securities.   The  reporting  person  on  this  cover  page,
                    however,  may be  deemed  a  beneficial  owner  only  of the
                    securities reported by it on this cover page.
------------====================================================================
    3       SEC USE ONLY

------------====================================================================
    4       CITIZENSHIP OR PLACE OF ORGANIZATION

            United States
-------------------------------------===========================================
        NUMBER OF           5        SOLE VOTING POWER

         SHARES                      -0-
                         ------------===========================================
      BENEFICIALLY          6        SHARED VOTING POWER

        OWNED BY                     3,100,094
                         ------------===========================================
          EACH              7        SOLE DISPOSITIVE POWER

        REPORTING                    -0-
                         ------------===========================================
      PERSON WITH           8        SHARED DISPOSITIVE POWER

                                     3,100,094
-------------------------------------===========================================
    9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            3,100,094
------------====================================================================
    10      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
            CERTAIN SHARES (See Instructions)
                                                                 [   ]
------------====================================================================
    11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

            5.9 %
------------====================================================================
    12      TYPE OF REPORTING PERSON (See Instructions)

            IN
------------====================================================================


                              Page 17 of 22 Pages



Item 1.  Issuer
         ------

         (a)  Name of Issuer:
              --------------

              CSG Systems International, Inc. (the "Company")

         (b)  Address of Issuer's Principal Executive Offices:
              -----------------------------------------------

              7887 East Belleview Avenue, Suite 1000, Englewood, Colorado 80111

Item 2.  Identity And Background.
         -----------------------

         Title Of Class Of Securities And CUSIP Number (Item 2(d) and (e))
         -----------------------------------------------------------------

         This statement  relates to Shares of Common Stock,  par value $0.01 per
share  (the  "Shares")  of the  Company.  The  CUSIP  number  of the  Shares  is
126349109.

         Name Of Persons Filing, Address Of Principal Business Office And
         ----------------------------------------------------------------
         Citizenship (Item 2(a), (b) and (c))
         ------------------------------------

         This statement is filed by the entities and persons  listed below,  all
of whom together are referred to herein as the "Reporting Persons."

         The Partnerships
         ----------------

                  (i)      Farallon Capital Partners, L.P., a California limited
                           partnership ("FCP"),  with respect to the Shares held
                           by it;

                  (ii)     Farallon  Capital  Institutional  Partners,  L.P.,  a
                           California limited partnership ("FCIP"), with respect
                           to the Shares held by it;

                  (iii)    Farallon Capital  Institutional  Partners II, L.P., a
                           California  limited  partnership  ("FCIP  II"),  with
                           respect to the Shares held by it;

                  (iv)     Farallon Capital Institutional  Partners III, L.P., a
                           Delaware  limited   partnership  ("FCIP  III"),  with
                           respect to the Shares held by it; and

                  (v)      Tinicum   Partners,   L.P.,   a  New   York   limited
                           partnership  ("Tinicum"),  with respect to the Shares
                           held by it.

         FCP,  FCIP,  FCIP II,  FCIP III and Tinicum  are  together  referred to
herein as the "Partnerships."

         The Management Company
         ----------------------


                              Page 18 of 22 Pages



                  (vi)     Farallon  Capital  Management,   L.L.C.,  a  Delaware
                           limited liability company (the "Management Company"),
                           with  respect to the Shares held by certain  accounts
                           managed  by  the  Management  Company  (the  "Managed
                           Accounts").

         The General Partner Of The Partnerships
         ---------------------------------------

                  (vii)    Farallon   Partners,   L.L.C.,   a  Delaware  limited
                           liability  company  which is the  general  partner of
                           each of the  Partnerships  (the  "General  Partner"),
                           with  respect  to the  Shares  held  by  each  of the
                           Partnerships.

         The Managing Members Of the General Partner And The Management Company
         ----------------------------------------------------------------------

                  (viii)   The  following  persons who are  managing  members of
                           both the General Partner and the Management  Company,
                           with  respect to the Shares held by the  Partnerships
                           and the Managed  Accounts:  David I. Cohen ("Cohen"),
                           Joseph  F.  Downes  ("Downes"),  William  F.  Duhamel
                           ("Duhamel"),  Richard B. Fried  ("Fried"),  Monica R.
                           Landry  ("Landry"),  William  F.  Mellin  ("Mellin"),
                           Stephen  L.  Millham  ("Millham"),  Thomas F.  Steyer
                           ("Steyer") and Mark C. Wehrly ("Wehrly").

         Cohen, Downes,  Duhamel,  Fried, Landry,  Mellin,  Millham,  Steyer and
Wehrly are together referred to herein as the "Individual Reporting Persons."

         The  citizenship of each of the  Partnerships,  the General Partner and
the  Management  Company is set forth above.  Each of the  Individual  Reporting
Persons is a United States citizen. The address of the principal business office
of each of the Reporting Persons is c/o Farallon Capital Management, L.L.C., One
Maritime Plaza, Suite 1325, San Francisco, California 94111.

Item 3.  If This Statement Is Filed Pursuant To Sections 240.13d-1(b)
         ------------------------------------------------------------
         or 240.13d-2(b) or (c), Check Whether The Person Filing Is An Entity
         --------------------------------------------------------------------
         Specified in (a) - (j):
         ----------------------

                  Not Applicable.

         If This Statement Is Filed Pursuant To Section 240.13d-1(c),
         ----------------------------------------------------------
         Check This Box. [X]
         --------------

Item 4.  Ownership
         ---------

         The  information  required  by Items 4(a) - (c) and set forth in Rows 5
through 11 of the cover page for each  Reporting  Person hereto is  incorporated
herein by reference for each such Reporting Person.

         The Shares reported hereby for the  Partnerships  are owned directly by
the Partnerships  and those reported by the Management  Company on behalf of the
Managed  Accounts  are owned  directly  by the  Managed  Accounts.  The  General
Partner,  as  general  partner  to the  Partnerships,  may be  deemed  to be the
beneficial  owner of all such Shares owned by the  Partnerships.  The


                              Page 19 of 22 Pages




Management Company, as investment adviser to the Managed Accounts, may be deemed
to be the beneficial owner of all such Shares owned by the Managed Accounts. The
Individual  Reporting  Persons,  as managing members of both the General Partner
and/or the Management Company,  may each be deemed to be the beneficial owner of
all such Shares held by the Partnerships and the Managed  Accounts.  Each of the
Management  Company,  the General Partner and the Individual  Reporting  Persons
hereby disclaims any beneficial ownership of any such Shares.

Item 5.  Ownership Of Five Percent Or Less Of A Class
         --------------------------------------------

                  Not Applicable.

Item 6.  Ownership Of More Than Five Percent On Behalf Of Another Person
         ---------------------------------------------------------------

                  Not Applicable.

Item 7.  Identification And Classification Of The Subsidiary Which Acquired The
         ----------------------------------------------------------------------
         Security Being Reported On By The Parent Holding Company
         --------------------------------------------------------

                  Not Applicable.

Item 8.  Identification And Classification Of Members Of The Group
         ---------------------------------------------------------

                  The Reporting Persons are filing this Schedule 13G pursuant to
         Rule  13d-1(c).  Consistent  with  Item 2 of the  cover  page  for each
         Reporting  Person above,  the Reporting  Persons  neither  disclaim nor
         affirm the existence of a group among them.

Item 9.  Notice Of Dissolution Of Group
         ------------------------------

                  Not Applicable.

Item 10. Certification
         -------------

                  By signing  below I certify  that, to the best of my knowledge
         and belief, the securities  referred to above were not acquired and are
         not  held  for the  purpose  of or  with  the  effect  of  changing  or
         influencing  the control of the issuer of the  securities  and were not
         acquired and are not held in connection with or as a participant in any
         transaction having that purpose or effect.


                              Page 20 of 22 Pages



                                   SIGNATURES


         After  reasonable  inquiry and to the best of our knowledge and belief,
the  undersigned  certify that the  information  set forth in this  statement is
true, complete and correct.

Dated:  April 9, 2003

                             /s/ Joseph F. Downes
                             ----------------------------------------
                             FARALLON PARTNERS, L.L.C.,
                             on its own behalf and as General Partner of
                             FARALLON CAPITAL PARTNERS, L.P.,
                             FARALLON CAPITAL INSTITUTIONAL PARTNERS, L.P.,
                             FARALLON CAPITAL INSTITUTIONAL PARTNERS II, L.P.,
                             FARALLON CAPITAL INSTITUTIONAL PARTNERS III, L.P.,
                             And TINICUM PARTNERS, L.P.,
                             By Joseph F. Downes
                             Managing Member


                             /s/ Joseph F. Downes
                             ----------------------------------------
                             FARALLON CAPITAL MANAGEMENT, L.L.C.
                             By Joseph F. Downes
                             Managing Member


                             /s/ Joseph F. Downes
                             ----------------------------------------
                             Joseph F. Downes, individually and as
                             attorney-in-fact for each of David I. Cohen,
                             William F. Duhamel, Richard B. Fried, Monica R.
                             Landry, William F. Mellin, Stephen L. Millham,
                             Thomas F. Steyer and Mark C. Wehrly.


         The Powers of Attorney,  each  executed by Cohen,  Mellin,  Millham and
Steyer  authorizing  Downes to sign and file this  Schedule 13G on each person's
behalf, which were filed with Amendment No. 1 to the Schedule 13D filed with the
Securities  and  Exchange  Commission  on January 20,  1998,  by such  Reporting
Persons with respect to the Units of Spiros  Development  Corporation  II, Inc.,
are hereby incorporated by reference.  The Powers of Attorney,  each executed by
Duhamel and Fried authorizing  Downes to sign and file this Schedule 13G on each
person's behalf, which were filed with Amendment No. 7 to the Schedule 13D filed
with  the  Securities  and  Exchange  Commission  on  February  9,  1999 by such
Reporting Persons with respect to the Callable Class A Common Stock of Crescendo
Pharmaceuticals  Corporation, are hereby incorporated by reference. The Power of
Attorney  executed  by Mark C. Wehrly  authorizing  Downes to sign and file this
Schedule 13G on his behalf, which was filed with Amendment No. 4 to the Schedule
13D filed with the Securities and Exchange Commission on


                              Page 21 of 22 Pages



January 18, 2000,  by such  Reporting  Person with respect to the Class A Common
Stock of  Momentum  Business  Applications,  Inc.,  is  hereby  incorporated  by
reference. The Power of Attorney executed by Monica R. Landry authorizing Downes
to sign and file this  Schedule  13G on her  behalf,  which  was filed  with the
Schedule 13G filed with the  Securities  and Exchange  Commission on January 22,
2001,  by such  Reporting  Person with respect to the Common Stock of Korn/Ferry
International, is hereby incorporated by reference.


                              Page 22 of 22 Pages