Exhibit 12.1

Aon Corporation and Consolidated Subsidiaries

Combined With Unconsolidated Subsidiaries

Computation of Ratio of Earnings to Fixed Charges

	Three Months Ended
	Mar. 31,				Years Ended December 31,
(millions except ratios)	2009		2008		2008		2007			2006		2005		2004
Income from continuing operations before income taxes and non-controlling interest	$	343	$	258	$	879	$	1,025		$	738	$	567	$	519
Less: Earnings from unconsolidated entities under the equity method of accounting	—		—		5		6			5		7		3
Add back fixed charges:
Interest on indebtedness	29		33		126		138			129		125		136
Interest on FIN 48 liabilities	—		—		—		(2		)	—		—		—
Portion of rents representative of interest factor	9		12		47		75			79		71		73
Income as adjusted	$	381	$	303	$	1,047	$	1,230		$	941	$	756	$	725
Fixed charges:
Interest on indebtedness	$	29	$	33	$	126	$	138		$	129	$	125	$	136
Portion of rents representative of interest factor	9		12		47		75			79		71		73
Total fixed charges	$	38	$	45	$	173	$	213		$	208	$	196	$	209
Ratio of earnings to fixed charges	10.0		6.7		6.1		5.8			4.5		3.9		3.5

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