Exhibit 15
Board of Directors and Stockholders
Aon Corporation
We are aware of the incorporation by reference in the Registration Statements of
Aon Corporation ("Aon") described in the following table of our report dated
August 10, 2000 relating to the unaudited condensed consolidated interim
financial statements of Aon Corporation that are included in its Form 10-Q for
the quarter ended June 30, 2000:
Registration Statement
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Form Number Purpose
---- ------ -------
S-8 33-27984 Pertaining to Aon's savings plan
S-8 33-42575 Pertaining to Aon's stock award plan and stock
option plan
S-8 33-59037 Pertaining to Aon's stock award plan and stock
option plan
S-4 333-21237 Offer to exchange Capital Securities of Aon Capital A
S-3 333-50607 Pertaining to the registration of 369,000 shares of
common stock
S-8 333-55773 Pertaining to Aon's stock award plan, stock option
plan and employee stock purchase plan
S-3 333-78723 Pertaining to the registration of debt securities,
preferred stock and common stock
Pursuant to Rule 436(c) of the Securities Act of 1933, our report is not a part
of the registration statements prepared or certified by accountants within the
meaning of Section 7 or 11 of the Securities Act of 1933.
/s/ ERNST & YOUNG LLP
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ERNST & YOUNG LLP
Chicago, Illinois
August 10, 2000
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