The question of how far a state should authorise the peacetime collection and use of intelligence gathered by secret agents and by interception of communications has long been a thorny issue of public policy. Today, new ethical and legal questions arise from the ability to access in bulk personal information from social media and from Internet use and to apply artificial intelligence trained algorithms to mine data for intelligence and law enforcement purposes. In his talk Sir David Omand, a former director of GCHQ, will lay out an ethical framework for thinking about these powerful developments in modern digital intelligence.