1. Name and Address of Reporting Person
   NAFUS, EDWARD C.
   7887 E. Belleview Avenue
   Suite 1000
   Englewood, CO 80111
   USA
2. Issuer Name and Ticker or Trading Symbol
   CSG Systems International, Inc. (CSGS)
3. IRS or Social Security Number of Reporting Person (Voluntary)
4. Statement for Month/Day/Year
   03/05/2003
5. If Amendment, Date of Original (Month/Day/Year)
6. Relationship of Reporting Person(s) to Issuer (Check all applicable)
   ( ) Director                   ( ) 10% Owner
   ( ) Officer (give title below) (X) Other (specify below)
   President
7. Individual or Joint/Group Filing (Check Applicable Line)
   (X) Form filed by One Reporting Person
   ( ) Form filed by More than One Reporting Person

TABLE I -- Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

+------------------------------+----------+----------+---------+--------------------------+--------------+-----------+------------+
|1. Title of Security          |2. Trans- |2A.Execu- |3. Trans-|4. Securities Acquired (A)|5. Amount of  |6. Owner-  |7. Nature   |
|                              |   action |   action |   action|   or Disposed of (D)     |Securities    |   ship    |   of In-   |
|                              |   Date   |   Date   |   Code  |                          |Beneficially  |   Form:   |   direct   |
|                              |          |          |         |                          |Owned         |   Direct  |   Bene-    |
|                              |  (Month/ |  (Month/ |         |                          |Following     |   (D) or  |   ficial   |
|                              |   Day/   |   Day/   +-----+---+-----------+---+----------+Reported      |   Indirect|   Owner-   |
|                              |   Year)  |   Year)  |Code |V  |Amount     |A/D|Price     |Transaction(s)|   (I)     |   ship     |
+------------------------------+----------+----------+-----+---+-----------+---+----------+--------------+-----------+------------+
                                                                                        
Common Stock                                                                               96796          D





TABLE II -- Derivative Securities Acquired, Disposed of, or Beneficially Owned

+----------+--------+-------+-------+---------+-----------+---------------------+----------------+----------+-------+-------+------+
|1.        |2.      |3.     |3A.    |4.       |5.         |6.                   |7.              |8.        |9.     |10.    |11.   |
|          |        |       |       |         |           |                     |                |          |Number |Owner- |      |
|          |        |       |       |         |           |                     |                |          |of     |ship   |      |
|          |        |       |       |         |           |                     |                |          |Deriv- |Form of|      |
|          |        |       |       |         |           |                     |Title and Amount|          |ative  |Deriv- |      |
|          |        |       |       |         |           |                     |of Underlying   |          |Secur- |ative  |Nature|
|          |Conver- |Trans- |Execu- |         |Number of  |                     |Securities      |          |ities  |Secur- |of    |
|          |sion or |action |tion   |         |Derivative |Date Exercisable     +-------+--------+          |Benefi-|ity:   |In-   |
|          |Exercise|Date   |Date   |         |Securities |and Expiration Date  |       |Amount  |          |cially |Direct |direct|
|          |Price of|       |       |Transac- |Acquired(A)|(Month/Day/Year)     |       |or      |          |Owned  |(D) or |Bene- |
|Title of  |Deriv-  |(Month/|(Month/|tion Code|Disposed(D)+----------+----------+       |Number  |Price of  |       |In-    |ficial|
|Derivative|ative   | Day/  | Day/  +------+--+-----+-----+Date Exer-|Expira-   |       |of      |Derivative|       |direct |Owner-|
|Security  |Security|Year)  |Year)  |Code  |V |(A)  |(D)  |cisable   |tion Date |Title  |Shares  |Security  |       |(I)    |ship  |
+----------+--------+-------+-------+------+--+-----+-----+----------+----------+-------+--------+----------+-------+-------+------+
                                                                                
Stock       $9.11    03/05/2         A         56096       03/05/2004 03/05/2013 Common  56096    $0.0000            D
Options              003                                                         Stock   
(Right to
buy)
Stock       $9.11    03/05/2         A         43904       03/05/2004 03/05/2013 Common  43904    $0.0000    100000  D
Options              003                                                         Stock   
(Right to
buy)
Stock       $21                                                       08/18/2008 Common                      160120  D
Options                                                                          Stock
(Right to
buy)

Explanation of Responses:


This stock option is exercisable in 4 equal installments.



SIGNATURE OF REPORTING PERSON
/s/ EDWARD C. NAFUS

DATE
03/07/2003