Fairfax County, officially the County of Fairfax, is a county in the Commonwealth of Virginia. It is part of Northern Virginia and borders both the city of Alexandria and Arlington County and forms part of the suburban ring of Washington, D.C. The county is predominantly suburban in character with some urban and rural pockets.
The county is home to the headquarters of several intelligence agencies such as the Central Intelligence Agency, National Geospatial-Intelligence Agency, National Reconnaissance Office, National Counterterrorism Center, and Office of the Director of National Intelligence as well as the headquarters of several aerospace manufacturing and defense industry giants. The county is also home to the flagship campus of George Mason University, and headquarters to seven Fortune 500 companies, including three in the Falls Church area, though not in the independent municipality of Falls Church.