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                                                                    Exhibit 31.1

                                  CERTIFICATION
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I, Joseph Esposito, certify that:

1.       I have reviewed this quarterly report on Form 10-Q for the period ended
         September 30, 2003 of eResearchTechnology, 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 this 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)) 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)   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; and

         (c)   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 that has materially
               affected, or is reasonably likely to materially affect, the
               registrant's internal control over financial reporting; and

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 auditors and the audit committee of
         registrant'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 registrant's
               ability to record, process, summarize and report financial
               information; and


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         (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:  November 7, 2003                           Joseph Esposito
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                                                  Joseph Esposito,
                                                  President and Chief Executive
                                                  Officer