It is widely acknowledged that cyber attacks will increasingly be a key aspect of future warfare and organised crime. This note explains the increasing threat to national security posed by the new “front” of the cyber realm of networked, digital activities (often internetbased) and sets out the Government’s response. The National Security Strategy (October 2010) has categorised “hostile attacks upon UK cyberspace by other states and large scale cyber crime” as one of its priority risks alongside terrorism, major accidents and natural hazards, and military crises. The associated Strategic Defence and Security Review (SDSR) responds to this with a new “transformative” £650m Cyber Security Programme to protect the UK from cyber attacks from both nation states and individuals.