Exhibit
23.1
CONSENT
OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We have
issued our report dated March 24, 2010 with respect to the consolidated
financial statements of ATS Corporation and subsidiary,
accompanying the consolidated financial statements included in the Annual Report
of ATS Corporation on Form 10-K for the year ended December 31,
2009. We hereby consent to the incorporation by reference of said
report in the Registration Statements of ATS Corporation on Forms S-3 (No.
333-124638) and S-8 (No. 333-146075).
/s/
GRANT THORNTON LLP
McLean,
Virginia
March 24,
2010