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                                                                    EXHIBIT 32.1

                            CERTIFICATION PURSUANT TO
                             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 on Form 10-K of Bookham, Inc. (the
"Company") for the period ended July 3, 2004 as filed with the Securities and
Exchange Commission on the date hereof (the "Report"), the undersigned, Giorgio
Anania, Chief Executive Officer of the Company, hereby certifies, pursuant to 18
U.S.C. Section 1350, that:

          (1) the Report fully complies with the requirements of Section 13(a)
     or 15(d) of the Securities Exchange Act of 1934; and

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

Date: September 16, 2004                       By: /s/ Giorgio Anania
                                                   ------------------
                                                   GIORGIO ANANIA
                                                   CHIEF EXECUTIVE OFFICER
                                                   (PRINCIPAL EXECUTIVE OFFICER)