One version of the Unified Intelligence Taskforce, also known as UNIT, existed on Pete's World.
President Harriet Jones eventually combined the organisations Torchwood and the Preachers into UNIT, which meant the Doctor, Jackie, Pete and Rose Tyler who were working for the Preachers now worked for UNIT.
Torchwood personnel such as Krista Lateef also worked for UNIT following the merger. Lateef would serve as a Brigadier in the organisation.
They had a base in Big Ben. (AUDIO: The Siege of Big Ben)