Document and Entity Information - shares	9 Months Ended
	Oct. 01, 2016	Oct. 28, 2016
Document and Entity Information
Entity Registrant Name	CRA INTERNATIONAL, INC.
Entity Central Index Key	0001053706
Document Type	10-Q
Document Period End Date	Oct. 01, 2016
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		8,273,616
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	Q3