Consolidated Statements of Comprehensive Income (Loss) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 29, 2013	Sep. 30, 2012	Oct. 02, 2011
Consolidated Statements of Comprehensive Income (Loss)
Net income (loss) including noncontrolling interests	$ (1,506)	$ 104,732	$ 92,982
Other comprehensive income (loss), net of tax
Foreign currency translation adjustments	(28,817)	26,486	(13,955)
Gain (loss) on cash flow hedge valuations	(389)	(194)	438
Other comprehensive income (loss), net of tax	(29,206)	26,292	(13,517)
Comprehensive income (loss) including noncontrolling interests	(30,712)	131,024	79,465
Net income attributable to noncontrolling interests	(635)	(352)	(2,943)
Foreign currency translation adjustments, net of tax	47	(29)	(492)
Comprehensive income attributable to noncontrolling interests	(588)	(381)	(3,435)
Comprehensive income (loss) attributable to Tetra Tech	$ (31,300)	$ 130,643	$ 76,030

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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