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                                                                    EXHIBIT 31.1

I, W. Bruce Turner, President and Chief Executive Officer of GTECH Holdings
Corporation (the "Company"), certify that:

(1)   I have reviewed this annual report on Form 10-K of the Company;

(2)   Based on my knowledge, this annual report does not contain any untrue
      statement of a material fact or omit to state a material fact necessary to
      make the statements made, in light of the circumstances under which such
      statements were made, not misleading with respect to the period covered by
      this annual report;

(3)   Based on my knowledge, the financial statements, and other financial
      information included in this annual report, fairly present in all material
      respects the financial condition, results of operations and cash flows of
      the Company as of, and for, the periods presented in this annual report;

(4)   The Company's other certifying officer and I are responsible for
      establishing and maintaining disclosure controls and procedures (as
      defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal
      control over financial reporting (as defined in Exchange Act Rules
      13a-15(f) and 15d-15(f)) for the Company and have:

            (a)   designed such disclosure controls and procedures, or caused
                  such disclosure controls and procedures to be designed under
                  our supervision, to ensure that material information relating
                  to the Company, including its consolidated subsidiaries, is
                  made known to us by others within those entities, particularly
                  during the period in which this annual report was being
                  prepared;

            (b)   designed such internal control over financial reporting, or
                  caused such internal control over financial reporting to be
                  designed under our supervision, to provide reasonable
                  assurance regarding the reliability of financial reporting and
                  the preparation of financial statements for external purposes
                  in accordance with generally accepted accounting principles;

            (c)   evaluated the effectiveness of the Company's disclosure
                  controls and procedures and presented in this annual report
                  our conclusions about the effectiveness of the disclosure
                  controls and procedures, as of the end of the period covered
                  by this annual report based on such evaluation; and

            (d)   disclosed in this annual report any change in the Company's
                  internal control over financial reporting that occurred during
                  the Company's most recent fiscal quarter (the Company's fourth
                  fiscal quarter in the case of this annual report) that has
                  materially affected, or its reasonably likely to materially
                  affect, the Company's internal control over financial
                  reporting; and

(5)   The Company's other certifying officer and I have disclosed, based on our
      most recent evaluation of internal control over financial reporting, to
      the Company's auditors and the audit committee of the Company's board of
      directors:

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            (a)   all significant deficiencies and material weaknesses in the
                  design or operation of internal control over financial
                  reporting which are reasonably likely to adversely affect the
                  Company's ability to record, process, summarize and report
                  financial information; and

            (b)   any fraud, whether or not material, that involves management
                  or other employees who have a significant role in the
                  Company's internal control over financial reporting.

                                          /s/ W. Bruce Turner
Date:  April 27, 2005                     --------------------------------------
                                          W. Bruce Turner
                                          President and Chief Executive Officer

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