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                                                                    Exhibit 23.1

                         CONSENT OF INDEPENDENT AUDITORS

      We consent to the reference to our firm under the caption "Experts" in the
Registration Statement (Form S-4 No. 333-_____) and related Prospectus of Arthur
J. Gallagher & Co. and subsidiaries for the registration of 5,940,329 shares of
its common stock and to the incorporation by reference therein of our reports
dated January 23, 2002, with respect to the consolidated financial statements
and schedule of Arthur J. Gallagher & Co. and subsidiaries included in its
Annual Report on Form 10-K for the year ended December 31, 2001 filed with the
Securities and Exchange Commission.



                                                    /S/ ERNST & YOUNG LLP
                                                  ------------------------------
                                                       Ernst & Young LLP


Chicago, Illinois
March 25, 2002


