EXHIBIT 32.1

           CERTIFICATIONS PURSUANT TO SECURITIES EXCHANGE ACT OF 1934
                         RULE 13a-14(b) OR 15d-14(b) AND
                            18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

         In connection with the annual report of ABM Industries Incorporated
(the "Company") on Form 10-K for the year ended October 31, 2003, as filed with
the Securities and Exchange Commission on the date hereof (the "Report"), Henrik
C. Slipsager, Chief Executive Officer of the Company, and George B. Sundby,
Chief Financial Officer of the Company, each certifies for the purpose of
complying with Rule 13a-14(b) or Rule 15d-14(b) of the Securities Exchange Act
of 1934 (the "Exchange Act") and Section 1350 of Chapter 63 of Title 18 of the
Untied States Code, that:

         (1)      the Report fully complies with the requirements of Section
                  13(a) or 15(d) of the Exchange Act; and

         (2)      the information contained in the Report fairly presents, in
                  all material respects, the financial condition and results of
                  operations of the Company.

January 14, 2004                        /s/ Henrik C. Slipsager
                                        ----------------------------------------
                                        Henrik C. Slipsager
                                        Chief Executive Officer
                                        (Principal Executive Officer)

January 14, 2004                        /s/ George B. Sundby
                                        ----------------------------------------
                                        George B. Sundby
                                        Chief Financial Officer
                                        (Principal Financial Officer)