National Security Agency (USA)

The National Security Agency (NSA) is the major US-based security agency with a focus on national security and terrorism. It conducts the major secret Internet surveillance programmes in the USA, legally justified under the Foreign Intelligence and Security Act (FISA).

The NSA has close relations with each of its equivalents in the 'Five Eyes', including GCHQ in the UK.

Special Source Operations

Runs PRISM and other Internet surveillance operations