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                                                                    EXHIBIT 23.1
 
                        CONSENT OF INDEPENDENT AUDITORS
 
  We consent to the reference to our firm under the caption "Experts" and to
the use of our report dated January 18, 1995 in the Registration Statement on
Form S-1 and related Prospectus of Arthur J. Gallagher & Co. and subsidiaries
for the registration of 750,000 shares of its Common Stock.
 
  We also consent to the incorporation by reference therein of our report with
respect to the consolidated financial statement schedule of Arthur J. Gallagher
& Co. and subsidiaries for the years ended December 31, 1994, 1993, and 1992
included in the 1994 Annual Report on Form 10-K filed with the Securities and
Exchange Commission.
 
                                          /s/ Ernst & Young LLP
                                          -------------------------------------
                                          Ernst & Young LLP
 
Chicago, Illinois
March 15, 1995
