EXHIBIT 31.1

                                  CERTIFICATION

I, Thomas J. Hook, certify that:

1.       I have reviewed this report on Form 10-K for the fiscal year ended
         December 29, 2006 of Greatbatch, Inc.;

2.       Based on my knowledge, this 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 the report;

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

4.       The registrant'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 registrant 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 registrant, including its
                      consolidated subsidiaries, is made known to us by others
                      within those entities, particularly during the period in
                      which this report is 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 registrant's disclosure
                      controls and procedures and presented in this report our
                      conclusions about the effectiveness of the disclosure
                      controls and procedures as of the end of the period
                      covered by this report based on such evaluation;

                  d.  Disclosed in this report any change in the registrant's
                      internal control over financial reporting that occurred
                      during the registrant's most recent fiscal quarter (the
                      registrant's fourth fiscal quarter in the case of an
                      annual report) that has materially affected, or is
                      reasonably likely to materially affect, the registrant's
                      internal control over financial reporting.



5.       The registrant's other certifying officer and I have disclosed, based
         on our most recent evaluation of internal control over financial
         reporting, to the registrant's auditor and the audit committee of
         registrant's board of directors (or persons performing the equivalent
         functions):

                  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 registrant'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 registrant's internal control over financial
                      reporting.



Date:  February 27, 2007
                                         /s/ Thomas J. Hook
                                         ---------------------------------
                                         Thomas J. Hook
                                         President and Chief Executive Officer
                                         (Principal Executive Officer)