<PAGE>

                                                                    EXHIBIT 31.1

                                 CERTIFICATIONS

I, Kevin E. Benson, certify that:

1.  I have reviewed this annual report on Form 10-K of Laidlaw International,
    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-14 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 (the registrant's
                  fourth quarter in the case of an annual report) 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 (or persons performing the equivalent functions):

    (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.


Date: December 1, 2003                     /s/ K. E. Benson
                                           -------------------------------------
                                           Kevin E. Benson
                                           President and Chief Executive Officer