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                                                                    EXHIBIT 31.1

                                  CERTIFICATION

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

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

(2)  Based on my knowledge, this quarterly 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 quarterly report;

(3)  Based on my knowledge, the financial statements, and other financial
     information included in this quarterly 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
     quarterly 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 quarterly 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 quarterly report our conclusions
          about the effectiveness of the disclosure controls and procedures, as
          of the end of the period covered by this quarterly report based on
          such evaluation; and

     (d)  disclosed in this quarterly report any change in the Company's
          internal control over financial reporting that occurred during the
          Company's most recent quarter that has materially affected, or is
          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:

     (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.


     Date: October 4, 2005              /s/ W. Bruce Turner
                                        ----------------------------------------
                                        W. Bruce Turner
                                        President and Chief Executive Officer