GTSI Corp. [GTSI] yesterday said it has acquired the federal information technology (IT) consulting firm Information Systems Consulting Group, a deal that expands its federal civilian presence and its professional services capabilities.

Terms of the deal were not disclosed. InSysCo is a woman-owned small business based in Virginia. The company’s primary customer is the Internal Revenue Service.

“The acquisition of InSysCo represents a significant step in executing our strategy of growing the professional services component of our business,” Sterling Phillips, president and CEO of GTSI, said in a statement. “With their CMMi Level 2 certification and long history of supporting software development at the Internal Revenue Service, InSysCo brings a new dimension of technical capability to deliver comprehensive information technology solutions to our customers.”

InSysCo has 110 employees. The company’s sales were not disclosed but they mainly provide senior subject matter experts, which means they bill at senior rates. InSysCo’s financial adviser on the deal was The McLean Group.