A reference to Tailored Access Operations in an XKeyscore slide
The Office of Tailored Access Operations (TAO), now Computer Network Operations, and structured as S32,[1] is a cyber-warfare intelligence-gathering unit of the National Security Agency (NSA).[2] It has been active since at least 1998, possibly 1997, but was not named or structured as TAO until "the last days of 2000," according to General Michael Hayden.[3][4][5]
TAO identifies, monitors, infiltrates, and gathers intelligence on computer systems being used by entities foreign to the United States.[6][7][8][9]