This chapter considers an array of new technologies developed for bulk collection and data analysis that are sometimes connected by critics with mass surveillance. While the use of such technologies can be compatible with democratic principles, the NSA’s system of bulk collection has been likened to that practised by the Stasi in the former German Democratic Republic. Drawing on Pettit’s concept of domination, we dispute the comparison, conceding nevertheless that bulk collection carries risks of intrusion, error, and damage to trust. Allowing that some surveillance is bound to be secret, we insist that secrecy must be limited, and subject to democratic oversight. Even if NSA-type surveillance is not a modern reincarnation of Stasi oppression failures of oversight make it objectionable from the perspective of democratic theory. More generally, surveillance technologies interfere with individual autonomy, which liberal democratic states are committed to protecting, whether the agent making use of them is a state or private company.