Quarterly Financial Information-Unaudited (Tables)

12 Months Ended

Sep. 30, 2012

	First Quarter		Second Quarter		Third Quarter		Fourth Quarter

	(in thousands, except per share data)
Fiscal Year 2012
Revenue	$	682,627	$	624,345	$	684,698	$	719,405
Operating income		36,093		35,543		46,261		48,470
Net income attributable to Tetra Tech		22,610		22,284		29,054		30,432
Earnings per share attributable to Tetra Tech⁽¹⁾:
Basic	$	0.36	$	0.35	$	0.46	$	0.48

Diluted	$	0.36	$	0.35	$	0.45	$	0.47

Weighted-average common shares outstanding:
Basic		62,433		63,072		63,387		63,623

Diluted		63,068		63,817		64,179		64,396

Fiscal Year 2011
Revenue	$	611,124	$	612,566	$	673,792	$	675,662
Operating income		34,325		29,256		39,408		43,433
Net income attributable to Tetra Tech		22,301		17,500		23,839		26,399
Earnings per share attributable to Tetra Tech⁽¹⁾:
Basic	$	0.36	$	0.28	$	0.38	$	0.42

Diluted	$	0.36	$	0.28	$	0.38	$	0.42

Weighted-average common shares outstanding:
Basic		61,665		62,121		62,203		62,310

Diluted		62,443		62,945		62,934		62,864

⁽¹⁾: The sum of the quarterly EPS may not add up to the full-year EPS due to rounding.