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                                                                    Exhibit 12.1


                            CERTIFICATION PURSUANT TO
                     SECURITIES EXCHANGE ACT RULE 13A-14(a)

I, Micheline Bouchard, certify that:

     1.   I have reviewed this annual report on Form 20-F of ART Advanced
          Research Technologies Inc. ("Registrant");

     2.   Based on my knowledge, this annual 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 annual report;

     3.   Based on my knowledge, the financial statements, and other financial
          information included in this annual 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 annual 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 their subsidiaries, is
                    made known to us by others within those entities,
                    particularly during the period in which this annual report
                    is being prepared;

               (b)  [Paragraph omitted pursuant to SEC Release Nos. 33-8238 and
                    34-47986]

               (c)  evaluated the effectiveness of the Registrant's disclosure
                    controls and procedures and presented in this annual 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

               (d)  disclosed in this annual 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


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     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 the
          Registrant's board of directors:

               (a)  all significant deficiencies and material weaknesses 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: March 31, 2005

                                  /s/ Micheline Bouchard
                                  ----------------------------------------------
                                  Name:    Micheline Bouchard
                                  Title:   President and Chief Executive Officer