Association of Former Intelligence Officers (AFIO). The AFIO was incorporated in 1975 as a 501(c)3 non-profit, non-political, educational association for current and former intelligence professionals and supporters of the US intelligence community.

Bletchley Park. During the Second World War, Bletchley Park was the site of the United Kingdom's main decryption establishment, the Government Code and Cypher School (GC&CS), where ciphers and codes of several Axis countries were decrypted, most importantly the ciphers generated by the German Enigma and Lorenz machines. It also housed Station X, a secret radio intercept station,and also a message sending station.

 Bureau of Intelligence and Research (INR). INR is a branch of the Department of State and has a primary mission to harness intelligence to serve U.S. diplomacy. Drawing on all-source intelligence, INR provides value-added independent analysis of events to Department policymakers; ensures that intelligence activities support foreign policy and national security purposes; and serves as the focal point in the Department for ensuring policy review of sensitive counterintelligence and law enforcement activities.

 Central Intelligence Agency (CIA). Can be found at http://www.cia.gov. (For some reason the CIA doesn't like linking to their site.) Official site provides news and information, publications, offices of the CIA, and careers. Includes links to their World Factbook, chiefs of state, and studies in intelligence.

Defense Intelligence Agency (DIA). The Defense Intelligence Agency (DIA) is a member of the U.S. Intelligence Community, and is the central producer and manager of military intelligence for the United States Department of Defense (DoD), employing over 16,500 U.S. military and civilian employees worldwide.

Director of National Intelligence (DNI). The idea of a Director of National Intelligence (DNI) dates to 1955 when a blue-ribbon study commissioned by Congress recommended that the Director of Central Intelligence employ a deputy to run the CIA so that the director could focus on coordinating the overall intelligence effort. This notion emerged as a consistent theme in many subsequent studies of the Intelligence Community commissioned by both the legislative and executive branches over the next five decades.

FBI Vault. The FBI's Vault is an electronic reading room, containing 6,700 documents and other media that have been scanned from paper into digital copies so you can read them instantly. Requires a PDF reader.

International Spy Museum, Washington DC. The story of spies, intelligence operations and deceptions that changed the course of history are featured in exhibits at one of DC's newest museums.

Intel News. Specialists in the field of espionage and intelligence, Joseph Fitsanakis and Ian Allen filter through the melodrama and sensationalism of the daily news to bring to the surface intelligence-related developments that rarely make news headlines.

Israel's Institute for Intelligence and Special Operations (Mossad). The Institute for Intelligence and Special Operations, otherwise known as the Mossad, has been appointed by the State of Israel to collect information, analyze intelligence, and perform special covert operations beyond its borders.

KGB Documents. Historians from Latvia, Estonia and Lithuania have come together to make public KGB documents from the years of the occupation of the three countries. The documents on this site are generally in Russian.

National Reconnaissance Office (NRO). The National Reconnaissance Office (NRO), located in Chantilly, Virginia, designs, builds, and operates the spy satellites of the United States government, and coordinates the analysis of aerial surveillance and satellite imagery from several intelligence and military agencies.

National Security Archive. An independent non-governmental research institute and library located at The George Washington University. The Archive collects and publishes declassified information via the FOIA.

NSA Verona Documents. From the National Security Agency. These are the scanned images of the VENONA documents which have been declassified.

Office of Strategic Services (OSS) Society. The OSS Society offers research assistance in response to requests from historians, educators, students, US military and intelligence organizations, and descendants of OSS veterans. The OSS Society also publishes the OSS Society Journal that is made available to members of the U.S. intelligence community and U.S. Special Operations Forces.

 Records of the Office of Strategic Services (OSS). The National Archive and Records Administration (NARA) page referencing documents specifically related to OSS operations during the Second World War.

Spy Blog. This United Kingdom based blog attempts to draw public attention to, and comments on, some of the current trends in ever cheaper and more widespread surveillance technology.

United Kingdom's Government Communications Headquarters (GCHQ). The official site of the UK's Government Communications Headquarters which is the center for Her Majesty's Government's Signal Intelligence (SIGINT) activities.

 United Kingdom's Secret Intelligence Service (MI-6). The United Kingdom's version of the CIA, MI-6's website has a number of articles about the service's history and news about the agency.

United Kingdom's Security Service (MI-5). The Security Service is responsible for protecting the United Kingdom against threats to national security. This website provides information about the Security Service, the threats it counters, links to sources of security advice and details of careers with the Service.

Wired's Danger Room. The Wired web site keeps track of espionage and national security news stories.