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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 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: January 4, 2006                      /s/ W. Bruce Turner
                                           -------------------------------------
                                           W. Bruce Turner
                                           President and Chief Executive Officer