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Exhibit 23(b)
CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS
We consent to the reference to our firm under the caption "Experts" in the
Registration Statement (Form S-3) and related Prospectus of Aon Corporation for
the registration of 3,864,824 shares of its common stock and to the
incorporation by reference therein of our reports dated February 8, 2000, with
respect to the consolidated financial statements of Aon Corporation
incorporated by reference in its Annual Report (Form 10-K) for the year ended
December 31, 1999 and the related financial statement schedules included
therein, filed with the Securities and Exchange Commission.
/s/ Ernst & Young LLP
Chicago, Illinois
November 2, 2000
