Government Communications Headquarters, commonly known as GCHQ, is an intelligence and security organization responsible for providing SignalsIntelligence(SIGINT) and information assurance to the government and armed forces of the United Kingdom. Based in "The Doughnut" in the suburbs of Cheltenham, GCHQ is the responsibility of the country's Secretary of State for Foreign and Commonwealth Affairs, but it is not a part of the Foreign Office and its Director ranks as a Permanent Secretary.

In 2013, GCHQ received considerable media attention when the former National Security Agency contractor Edward Snowden revealed that the agency was in the process of collecting all online and telephone data in the UK via the Tempora programme. Snowden's revelations began a spate of ongoing disclosures of global surveillance. The Guardian newspaper was then forced to destroy all incriminating files given to them by Snowden because of the threats of lawsuits from the UK Government.[1]

Sources

1. https://en.wikipedia.org/wiki/GCHQ