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                                                                    EXHIBIT 31.2


           CERTIFICATION OF CHIEF FINANCIAL OFFICER OF THE REGISTRANT,
          PURSUANT TO 17 CFR 240.13a - 14(a) OR 17 CFR 240.15d - 14(a)


I, Ray E. Schmitz, certify that:


     1.   I have reviewed this annual report on Form 10-K of Dynamex Inc.;

     2.   Based on my knowledge, this annual report does not contain any untrue
          statements 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 Dynamex Inc. 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-14 and 15d-14) for the registrant
          and we have:

               a.   Designed such 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 annual report
                    is being prepared;

               b.   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

               c.   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
                    (the registrant's fourth fiscal quarter in the case of this
                    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 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 controls which could
                    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 controls over financial reporting.




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Date: October 20, 2003



/s/ RAY E. SCHMITZ
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Name: Ray E. Schmitz
Title: Vice President and Chief Financial Officer