Counterintelligence in the context of "Military Intelligence Civilian Excepted Career Program"

The National Security Agency (NSA) is an intelligence agency of the United States Department of Defense, under the authority of the director of national intelligence (DNI). The NSA is responsible for global monitoring, collection, and processing of information and data for global intelligence and counterintelligence purposes, specializing in a discipline known as signals intelligence (SIGINT). The NSA is also tasked with the protection of U.S. communications networks and information systems. The NSA relies on a variety of measures to accomplish its mission, the majority of which are clandestine. The NSA has roughly 32,000 employees.

Originating as a unit to decipher coded communications in World War II, it was officially formed as the NSA by President Harry S. Truman in 1952. Between then and the end of the Cold War, it became the largest of the U.S. intelligence organizations in terms of personnel and budget. Still, information available as of 2013 indicates that the Central Intelligence Agency (CIA) pulled ahead in this regard, with a budget of $14.7 billion. The NSA currently conducts worldwide mass data collection and has been known to physically bug electronic systems as one method to this end. The NSA is also alleged to have been behind such attack software as Stuxnet, which severely damaged Iran's nuclear program. The NSA, alongside the CIA, maintains a physical presence in many countries across the globe; the CIA/NSA joint Special Collection Service (a highly classified intelligence team) inserts eavesdropping devices in high-value targets (such as presidential palaces or embassies). SCS collection tactics allegedly encompass "close surveillance, burglary, wiretapping, [and] breaking".

The Federal Bureau of Investigation (FBI) is the primary federal law enforcement agency in the United States and also the American domestic intelligence and security service. An agency of the United States Department of Justice, the FBI is a member of the U.S. Intelligence Community and reports to both the attorney general and the director of national intelligence. A leading American counterterrorism, counterintelligence, and criminal investigative organization, the FBI has jurisdiction over violations of more than 200 categories of federal crimes. The FBI maintains a list of its top 10 most wanted fugitives.

Although many of the FBI's functions are unique, its activities in support of national security are comparable to those of the British MI5 and NCA and the Russian FSB. Unlike the Central Intelligence Agency (CIA), which has no law enforcement authority and is focused on intelligence collection abroad, the FBI is primarily a domestic agency, maintaining 56 field offices in major cities throughout the United States, and more than 400 resident agencies in smaller cities and areas across the nation. At an FBI field office, a senior-level FBI officer concurrently serves as the representative of the director of national intelligence.

The Praetorian Guard (Latin: cohortes praetoriae) was the imperial guard of the Imperial Roman army that served various roles for the Roman emperor including being a bodyguard unit, counterintelligence, crowd control and gathering military intelligence.

During the Roman Republic, the Praetorian Guards were escorts for high-ranking political officials (senators and procurators) and were bodyguards for the senior officers of the Roman legions. In 27 BC, after Rome's transition from republic to empire, the first emperor of Rome, Augustus, designated the Praetorians as his personal security escort. For three centuries, the guards of the Roman emperor were also known for their palace intrigues, by whose influence upon imperial politics the Praetorians could overthrow an emperor and then proclaim his successor as the new caesar of Rome. In AD 312, Constantine the Great disbanded the cohortes praetoriae and destroyed their barracks at the Castra Praetoria.

A cover in foreign, military or police human intelligence or counterintelligence is the ostensible identity and role or position in an infiltrated organization assumed by a covert agent during a covert operation.

The Pontifical Swiss Guard, also known as the Papal Swiss Guard or simply Swiss Guard, is an armed forces, guard of honour, and protective security unit, maintained by the Holy See to protect the Pope and the Apostolic Palace within the territory of the Vatican City State. Established in 1506 under Pope Julius II, it is among the oldest military units in continuous operation and is sometimes called "the world's smallest army".

The Swiss Guard is recognised by its Renaissance-era dress uniform, consisting of a tunic striped in red, dark blue, and yellow; high plumed helmet; and traditional weapons such as the halberd. Guardsmen perform their protective duties in functional attire and with modern firearms. Since the assassination attempt on Pope John Paul II in 1981, the Guard has placed greater emphasis on its nonceremonial roles and has sought more training in anti-irregular military counterintelligence, commando-style raids, counter-sniper tactics, counterterrorism, close-quarters battle, defusing and disposal of bombs, executive protection, hostage rescue, human intelligence, medical evacuation, reconnaissance, tactical driving, tactical medical services, and tactical fast shooting by small arms.

The People's Commissariat for Internal Affairs (Russian: Народный комиссариат внутренних дел, romanized: Narodnyy komissariat vnutrennikh del, IPA: [nɐˈrodnɨj kəmʲɪsərʲɪˈat ˈvnutrʲɪnʲɪɣ dʲel]), abbreviated as NKVD (Russian: НКВД; listen), was the interior ministry and secret police of the Soviet Union from 1934 to 1946. The agency was formed to succeed the Joint State Political Directorate (OGPU) secret police organization, and thus had a monopoly on intelligence and state security functions. The NKVD is known for carrying out political repression and the Great Purge under Joseph Stalin, as well as counterintelligence and other operations on the Eastern Front of World War II. The head of the NKVD was Genrikh Yagoda from 1934 to 1936, Nikolai Yezhov from 1936 to 1938, Lavrentiy Beria from 1938 to 1946, and Sergei Kruglov in 1946.

First established in 1917 as the NKVD of the Russian SFSR, the ministry was tasked with regular police work and overseeing the country's prisons and labor camps. It was disbanded in 1930, and its functions dispersed among other agencies before being reinstated as a commissariat of the Soviet Union in 1934. During the Great Purge in 1936–1938, on Stalin's orders, the NKVD conducted mass arrests, imprisonment, torture, and executions of hundreds of thousands of Soviet citizens. The agency sent millions to the Gulag system of forced labor camps and, during World War II, carried out the mass deportations of hundreds of thousands of Poles, Balts, and Romanians, and millions of ethnic minorities from the Caucasus, to remote areas of the country, resulting in millions of deaths. Hundreds of thousands of NKVD personnel served in Internal Troops divisions in defensive battles alongside the Red Army, as well as in "blocking formations," preventing retreat. The agency was responsible for foreign assassinations, including that of Leon Trotsky.

The Ministry of State Security (MSS) is the principal civilian intelligence and security service of the People's Republic of China, responsible for foreign intelligence, counterintelligence, and political security of the Chinese Communist Party (CCP). One of the largest and most secretive intelligence organizations in the world, it maintains powerful semi-autonomous branches at the provincial, city, municipality and township levels throughout China. The ministry's headquarters, Yidongyuan, is a large compound in Beijing's Haidian district.

The origins of the MSS date to the beginnings of the CCP's Central Special Branch, replaced by the Central Committee Society Department from 1936 through the proclamation of the People's Republic in 1949. In 1955, the department was replaced with the Central Committee Investigation Department, which existed in various configurations through the Cultural Revolution to 1983, when it was merged with counterintelligence elements of the Ministry of Public Security (MPS) to form the MSS.

A security agency is a governmental organization that conducts intelligence activities for the internal security of a state. They are the domestic cousins of foreign intelligence agencies, and typically conduct counterintelligence to thwart other countries' foreign intelligence efforts.

For example, the United States Federal Bureau of Investigation (FBI) is an internal intelligence, security and law enforcement agency, while the Central Intelligence Agency (CIA) is an external intelligence service, which deals primarily with intelligence collection overseas. A similar relationship exists in Britain between MI5 and MI6.