Exhibit 12.1

Aon Corporation and Consolidated Subsidiaries

Combined With Unconsolidated Subsidiaries

Computation of Ratio of Earnings to Fixed Charges

	Six Months Ended
	June 30,					Years Ended December 31,
(millions except ratios)	2010			2009		2009		2008		2007		2006		2005
Income from continuing operations before provision for income taxes and noncontrolling interests	$	491		$	553	$	949	$	879	$	1,023	$	738	$	567
Less: Equity in earnings of less than 50% owned entities	8			2		11		5		6		5		7
Add back fixed charges:
Interest on indebtedness	67			55		122		126		138		129		125
Interest on uncertain tax positions	(2		)	—		2		—		2		—		—
Portion of rents representative of interest factor	21			20		48		47		75		79		71
Income as adjusted	$	569		$	626	$	1,110	$	1,047	$	1,232	$	941	$	756
Fixed charges:
Interest on indebtedness	$	67		$	55	$	122	$	126	$	138	$	129	$	125
Interest on uncertain tax positions	(2		)	—		2		—		2		—		—
Portion of rents representative of interest factor	21			20		48		47		75		79		71
Total fixed charges	$	86		$	75	$	172	$	173	$	215	$	208	$	196
Ratio of earnings to fixed charges	6.6			8.3		6.5		6.1		5.7		4.5		3.9

1