Earnings Per Share ("EPS") (Tables)

3 Months Ended

Jan. 01, 2012

Earnings Per Share ("EPS")

Schedule of number of weighted-average shares used to compute basic and diluted EPS

	Three Months Ended
	January 1,2012		January 2,2011
	(in thousands, except per share data)
Net income attributable to Tetra Tech	$	22,610	$	22,301
Weighted-average common shares outstanding - basic	62,433		61,665
Effect of dilutive stock options and unvested restricted stock	635		778
Weighted-average common stock outstanding - diluted	63,068		62,443
Earnings per share attributable to Tetra Tech:
Basic	$	0.36	$	0.36
Diluted	$	0.36	$	0.36