Interagency participation throughout the Combating Terrorism Technical Support Office's programs cannot be overstated. The ability to share information, reduce duplication, and leverage resources is the backbone of CTTSO.

The CTTSO collaborates with representatives from more than 100 organizations throughout the federal government, first responders, state and local law enforcement, and the intelligence community. Through this vast interagency collaboration, participants articulate user specific requirements and define approaches to the development of combating terrorism solutions.

Prominent interagency participants include the Department of Defense (all services, SOCOM, OSD, and the Combatant Commands), State, Homeland Security, Justice, Energy, Health and Human Services, Commerce, Agriculture, and Transportation; the intelligence community; other federal agencies; state and local governments; and private owners of infrastructure.