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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 Securities 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

5.   The Registrant's other certifying officer and I have disclosed, based on
     our most recent

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     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 of 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: April 24, 2006


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