Edward Joseph Snowden (born June 21, 1983) is an American former technical contractor for the United States National Security Agency (NSA) and a former employee of the Central Intelligence Agency (CIA) who leaked details of several top-secret US and British Government mass surveillance programmes to the press.

Snowden leaked the information, primarily to Glenn Greenwald of London’s The Guardian, in spring 2013 while employed as an “infrastructure analyst” at NSA contractor Booz Allen Hamilton. The Guardian in turn published a series of exposés in June–July 2013 and revealed programmes such as the interception of US and European telephone metadata and the PRISM and Tempora Internet surveillance programmes. Snowden’s leaks are said to rank among the most significant breaches in United States history.

Snowden’s leaks have been a subject of great controversy. Some have called Snowden a hero and a whistleblower, while others have called him a traitor. Snowden has defended his leaks as an effort “to inform the public as to that which is done in their name and that which is done against them”. Government officials have condemned his actions as having harmed US interests and its position in the War on Terror. Meanwhile, the media disclosures have fuelled debates in the United States and elsewhere over mass surveillance, government secrecy, and the balance between national security and information privacy in the post-9/11 era.

On June 14, 2013, US federal prosecutors charged Snowden with espionage and theft of government property.