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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                  SCHEDULE 13G


                   Under the Securities Exchange Act of 1934

                             (Amendment _________)*

                              Global Payments Inc.
--------------------------------------------------------------------------------
                                (Name of Issuer)

                                  Common Stock
--------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                    37940X102
                         ------------------------------
                                 (CUSIP Number)

                                December 31, 2001
--------------------------------------------------------------------------------
             (Date of Event Which Requires Filing of this Statement)


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

                                [X] Rule 13d-1(b)
                                [_] Rule 13d-1(c)
                                [_] Rule 13d-1(d)


*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).

                                     1 of 9


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----------------------------                         ------------------------
  CUSIP No. 37940X102               13G                 Page 2 of 9 Pages
           -----------
----------------------------                         ------------------------

------------------------------------------------------------------------------
      NAME OF REPORTING PERSON
 1    S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

      Liberty Wanger Asset Management, L.P. 36-3820584
------------------------------------------------------------------------------
      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
 2                                                              (a) [_]
      Not Applicable                                            (b) [_]
------------------------------------------------------------------------------
      SEC USE ONLY
 3
------------------------------------------------------------------------------
      CITIZENSHIP OR PLACE OF ORGANIZATION
 4
      Delaware
------------------------------------------------------------------------------
                          SOLE VOTING POWER
                     5
     NUMBER OF            None
      SHARES       -----------------------------------------------------------
                          SHARED VOTING POWER
   BENEFICIALLY      6
     OWNED BY             1,943,040
                   -----------------------------------------------------------
       EACH               SOLE DISPOSITIVE POWER
                     7
    REPORTING             None
      PERSON       -----------------------------------------------------------
                          SHARED DISPOSITIVE POWER
       WITH          8
                          1,943,040
------------------------------------------------------------------------------
      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 9
      1,943,040
------------------------------------------------------------------------------
      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
      Not Applicable                                                [_]
------------------------------------------------------------------------------
      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
11
      5.3%
------------------------------------------------------------------------------
      TYPE OF REPORTING PERSON*
12
      IA
------------------------------------------------------------------------------

                      *SEE INSTRUCTION BEFORE FILLING OUT!


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-----------------------------                      -----------------------------
  CUSIP No. 37940X102                                   Page 3 of 9 Pages
           --------------
-----------------------------                      -----------------------------

------------------------------------------------------------------------------
      NAME OF REPORTING PERSON
 1    S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

      WAM Acquisition GP, Inc.
------------------------------------------------------------------------------
      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
 2                                                              (a) [_]
      Not Applicable                                            (b) [_]
------------------------------------------------------------------------------
      SEC USE ONLY
 3
------------------------------------------------------------------------------
      CITIZENSHIP OR PLACE OF ORGANIZATION
 4
      Delaware
------------------------------------------------------------------------------
                          SOLE VOTING POWER
                     5
     NUMBER OF            None
      SHARES       -----------------------------------------------------------
                          SHARED VOTING POWER
   BENEFICIALLY      6
     OWNED BY             1,943,040
                   -----------------------------------------------------------
       EACH               SOLE DISPOSITIVE POWER
                     7
    REPORTING             None
      PERSON       -----------------------------------------------------------
                          SHARED DISPOSITIVE POWER
       WITH          8
                          1,943,040
------------------------------------------------------------------------------
      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 9
      1,943,040
------------------------------------------------------------------------------
      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
      Not Applicable                                                [_]
------------------------------------------------------------------------------
      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
11
      5.3%
------------------------------------------------------------------------------
      TYPE OF REPORTING PERSON*
12
      CO
------------------------------------------------------------------------------

                      *SEE INSTRUCTION BEFORE FILLING OUT!


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Item 1(a)     Name of Issuer:

                   Global Payments Inc.

Item 1(b)     Address of Issuer's Principal Executive Offices:

                   Four Corporate Square
                   Atlanta, Georgia
                   30329-2009

Item 2(a)     Name of Person Filing:

                   Liberty Wanger Asset Management, L.P. ("WAM")
                   WAM Acquisition GP, Inc., the general partner of WAM
                    ("WAM GP")

Item 2(b)     Address of Principal Business Office:

                   WAM and WAM GP are located at:

                   227 West Monroe Street, Suite 3000
                   Chicago, Illinois  60606

Item 2(c)     Citizenship:

                   WAM is a Delaware limited partnership; and WAM GP is
                   a Delaware corporation.

Item 2(d)     Title of Class of Securities:

                   Common Stock

Item 2(e)     CUSIP Number:

                   37940X102

Item 3        Type of Person:

                   (e)   WAM is an Investment Adviser registered under section
                         203 of the Investment Advisers Act of 1940; WAM GP is
                         the General Partner of the Investment Adviser.

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Item 4        Ownership (at December 31, 2001):

                  (a)  Amount owned "beneficially" within the meaning of
                       rule 13d-3:

                       1,943,040

                  (b)  Percent of class:

                       5.3 % (based on 36,571,011 shares outstanding as of
                       January 8, 2002)

                  (c)  Number of shares as to which such person has:

                          (i)   sole power to vote or to direct the vote:  none
                         (ii)   shared power to vote or to direct the vote:
                                1,943,040
                        (iii)   sole power to dispose or to direct the
                                disposition of:  none
                         (iv)   shared power to dispose or to direct disposition
                                of:  1,943,040

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:

                  The shares reported herein have been acquired on behalf of
                  discretionary clients of WAM. Persons other than WAM and WAM
                  GP are entitled to receive all dividends from, and proceeds
                  from  the sale of, those shares.

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:

                  Not Applicable

Item 9        Notice of Dissolution of Group:

                  Not Applicable

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Item 10     Certification:

                By signing below I certify that, to the best of my knowledge and
            belief, the securities referred to above were acquired and are held
            in the ordinary course of business and 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.

                                     6 of 9


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                                    Signature
                                    ---------

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

Date: February 12, 2002


               The undersigned corporation, on the date above written, agrees
               and consents to the joint filing on its behalf of this Schedule
               13G in connection with its beneficial ownership of the security
               reported herein.


                                    WAM Acquisition GP, Inc.
                                        for itself and as general partner of
                                        LIBERTY WANGER ASSET MANAGEMENT, L.P.



                                    By: /s/ Bruce H. Lauer
                                        ----------------------------------------
                                            Bruce H. Lauer
                                            Senior Vice President and Secretary

                                     7 of 9


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                                  Exhibit Index
                                  -------------

Exhibit 1           Joint Filing Agreement dated as of February 12, 2002 by
                    and between Liberty Wanger Asset Management, L.P. and WAM
                    Acquisition GP, Inc.

                                     8 of 9


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                                                                       EXHIBIT 1

                             JOINT FILING AGREEMENT

         The undersigned hereby agree to the joint filing of the Schedule 13G to
which this Agreement is attached.

                  Dated: February 12, 2002


                                  WAM Acquisition GP, Inc.
                                      for itself and as general partner of
                                      LIBERTY WANGER ASSET MANAGEMENT, L.P.



                                  By:  /s/ Bruce H. Lauer
                                       -----------------------------------------
                                           Bruce H. Lauer
                                           Senior Vice President and Secretary

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