Exhibit 23.1 [LETTERHEAD OF SAMSON BELAIR DELOITTE & TOUCHE] INDEPENDENT AUDITORS' CONSENT We hereby consent to the use in this Registration Statement of CGI Group Inc. on Form F-4 of our report dated November 7, 2000 (except for Notes 7 a), 15 a) to e), and 17 which are dated March 30, 2001) with respect to the audited consolidated balance sheets of CGI Group Inc. as at September 30, 2000 and 1999 and the statements of earnings, retained earnings and cash flows for each of the years in the three-year period ended September 30, 2000 prepared in accordance with Canadian generally accepted accounting principles. We also consent to the incorporation by reference in this Registration Statement of CGI Group Inc. on Form F-4 of our report dated November 7, 2000 with respect to the audited consolidated balance sheets of CGI Group Inc. as at September 30, 2000 and 1999 and the statements of earnings, retained earnings and cash flows for each of the years in the three-year period ended September 30, 2000 prepared in accordance with Canadian generally accepted accounting principles, which report is incorporated by reference herein from CGI's Annual Report on Form 40-F for the year ended September 30, 2000. We also consent to the reference to us under the headings "Experts" in the Registration Statement (Signed) Samson Belair/Deloitte & Touche Chartered Accountants Montreal, Quebec March 30, 2001