What fictional agency employs Jack Bauer in early seasons of 24?

What fictional agency employs Jack Bauer in early seasons of 24? The answer is the Counter Terrorist Unit, usually abbreviated CTU.

CTU is the fictional U.S. government agency at the center of much of 24. Its Los Angeles office combines intelligence gathering, communications, and field operations aimed at preventing terrorist attacks. Jack Bauer begins the series as a senior CTU agent and later leads the organization during several national emergencies.

The agency is not the FBI, CIA, or NSA, although the show frequently places CTU personnel alongside those real-world institutions. CTU’s fictional structure includes local offices, regional divisions, and a national district, giving Jack access to analysts, tactical teams, surveillance systems, and government contacts.

The series’ first season follows Bauer as he tries to protect presidential candidate David Palmer while dealing with a conspiracy targeting his family. CTU remains the show’s main workplace even when later seasons move Jack into other agencies or independent missions.