The Counter Terrorist Unit (CTU) is a fictional elite branch of the United States Central Intelligence Agency (CIA) created after the 1993 World Trade Center Attack. Its headquarters are in Washington D.C. with satellite operations in major cities where threats are likely. CTU’s primary mission is to disrupt and destroy foreign and domestic terror cells hostile to the United States, as well as protect the U.S. from terror attacks. With an office in nearly every major city of the U.S., CTU also has a role in creating security policy and fighting groups of organized crime that fund terrorism.^[1]

CTU offices are run by a Director, also called the Special Agent in Charge, to whom the Director of Field Operations and the Chief of Staff report. The CTU offices report to a District Office, overseen by the District Director. District offices cover a larger amount of territory in their jurisdiction. Finally, the District office and all other offices report to a Division Headquarters, overseen by a Regional Director. This title implies that each Division Headquarters has jurisdiction over an entire region of the United States. It is likely that the Division Headquarters, run first by Ryan Chappelle and then Bill Buchanan, were responsible for the Pacific Coast, with other Divisions taking responsibility for other parts of the country.

CTU is also mentioned in the 2004 production of The Punisher as a previous place of employment for Frank Castle, probably an homage to 24.