Post 200 The 2011 guide to the region's top businesses

CACI's headquarters in Arlington. (Manuel Balce Ceneta /AP)

Public companies and financial services

CACI International

The government contractor focuses on a broad range of professional services, from program management to information technology to cybersecurity. CACI has a long history of acquiring businesses. Among its purchases in 2011 were Reston-based Advanced Programs Group, which provides Oracle services to the federal government, and Rockville-based Paradigm Holdings, which focuses on cybersecurity and IT services. CACI also acquired Fulton, Md.-based cybersecurity firm Pangia Technologies.

Trivia

The original name of the company was California Analysis Center, Inc. CACI moved its headquarters to the D.C. area in 1972.