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                                                                    EXHIBIT 31.2

                                 CERTIFICATION

I, Todd E. Simpson, certify that:

1.       I have reviewed this quarterly report on Form 10-Q of Targeted Genetics
         Corporation;

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 report;

3.       Based on my knowledge, the condensed consolidated 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 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 we 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, to the registrant's auditors and the
         audit committee of the registrant's board of directors (or persons
         performing the equivalent function):

         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.

April 28, 2004                  /s/ Todd E. Simpson
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Date                            Todd E. Simpson
                                Vice President, Finance and Administration,
                                Chief Financial Officer, Secretary and Treasurer
                                (Principal Financial and Accounting Officer)