Five Eyes is a naval Command, Control, Communications and Computers (C4) interoperability organization involving the Anglosphere nations of Australia, Canada, New Zealand, the United Kingdom, and the United States,the most exclusive intelligence sharing club in the world.
Five Eyes grew from UK-US intelligence cooperation in the Second World War, matured during the Cold War, and continues to protect the national interests of all members today. The evolving international security environment indicates a need for enhanced Five Eyes intelligence cooperation in the future.
The five nations have agreed not to spy on each other, and in many outposts around the world, Five Eyes agencies work side-by-side, allowing for information to be shared quickly.
In Five Eyes, the U.S. boasts the most advanced technical abilities and the biggest budget. Britain is a leader in traditional spying, thanks in part to its reach into countries that were once part of it colonial empire.
Australia has excelled in gathering regional signals and intelligence, providing a window into the growing might of Asia.
Canadians, Australians and New Zealanders can sometimes prove useful spies because they don’t come under the same scrutiny as their British and American counterparts.
Britain is home to one of the world’s largest eavesdropping centers, located about 300 km northwest of London at Menwith Hill. It’s run by the NSA but hundreds of British employees work there, including analysts from Britain’s eavesdropping agency, the Government Communications Headquarters.
Australia is home to Pine Gap, a sprawling satellite tracking station located in the remote center of the country, where NSA officials work side-by-side with scores of locals. The U.S. also posts three or four analysts at a time in New Zealand, home to the small Waihopai and Tangimoana spy stations.
The Guardian cited British intelligence memos leaked by former National Security Agency contractor Edward Snowden to claim that UK spies were tapping into the world's network of fibre optic cables to deliver the "biggest internet access" of any member of the Five Eyes