What Is Echelon?

Echelon is a global surveillance system operated by a consortium of five English-speaking countries ~ the United States, the United Kingdom, Canada, Australia, and New Zealand. It was formed in 1947 under an agreement known as 'UKUSA.' Echelon specialises in signals intelligence, or SIGINT. Through a network of giant listening stations, Echelon intercepts, records and analyses vast numbers of communications worldwide, including telephone calls, faxes, and emails.

Although the governments involved in the Echelon system are extremely secretive about it, some details of its method of operation have leaked out over the years thanks to whistleblowers and investigative reporting. It is believed to work largely on the basis of keywords. Sophisticated software scans the raw communications data, searching for target words and phrases; if found, the communication is flagged for further analysis.

Critics have persistently alleged that Echelon has been used, not only for legitimate national security purposes, but for the targeting of political opponents.