The ManTech Defense Systems Group consists of more than 2,300 professionals, the majority of which hold TS/SCI clearances. The DSG is headquartered in Chantilly, Virginia has a 40,000 square foot facility which includes a full service warehouse, a TS facility, and a 1,400 square foot SCIF. In addition to our Chantilly location, DSG also has more than 100 CONUS and OCONUS locations.

The DSG member subsidiaries include:

• ManTech Telecommunications and Information Systems Corporation (MTISC)



• ManTech Systems Engineering Corporation (MSEC)