The United States Secret Service is a federal law enforcement agency under the Department of Homeland Security charged with conducting criminal investigations and protecting U.S. political leaders, their families, and visiting heads of state or government. Until 2003, the Secret Service was part of the Department of the Treasury, as the agency was founded in 1865 to combat the then-widespread counterfeiting of U.S. currency. President Abraham Lincoln signed the legislation on April 14, 1865, just a few hours before he was assassinated. In 1901, the Secret Service was also assigned to presidential protection duties.
The Diplomatic Security Service (DSS) is the principal security and law enforcement agency of the United States Department of State (DOS). As the operational division of DOS Bureau of Diplomatic Security, its primary mission is to provide security to protect diplomatic assets, personnel, and information, and combat visa and passport fraud. DSS also conducts counterterrorism, counterintelligence, cybersecurity and criminal investigations domestically and abroad.
The Specialist Firearms Command is the firearms unit of the Metropolitan Police. The Command is responsible for providing a firearms-response capability, assisting the rest of the service which is not routinely armed.
The Federal Protective Service (FPS) is a federal law enforcement agency of the United States Department of Homeland Security (DHS). It is also "the federal agency charged with protecting and delivering integrated law enforcement and security services to facilities owned or leased by the General Services Administration (GSA)"—over 9,000 buildings—and their occupants.
The Nucleo Operativo Centrale di Sicurezza(NOCS) (English: Central Security Task Group) is the police tactical unit of the Polizia di Stato, one of Italy's national police forces. It operates under the command of the Direzione Centrale della Polizia di Prevenzione (English: Central Directorate for the Anti-Terrorism Police).
The Grupo Especial de Operaciones Federales is a police tactical unit of the Policía Federal Argentina trained to strategically perform counterterrorist and counternarcotics missions. It is also used for VIP protection and hostage rescue situations.
Beredskapstroppen, callsign "Delta", is the police tactical unit of the Norwegian Police Service. Its members are trained to perform dangerous operations such as high-risk arrests and hostage situations. It is organizationally part of Oslo Police District, but is responsible for the whole country, including oil installations in the North Sea.
The 1er Batallón de Combate-Grupo Especial Uno is a tactical assault division of the Argentine Federal Police. It depends directly of the Infantry Guard Corps, and its motto is Nihil Obstat.
The Special Operations Group is the police tactical unit of the Public Security Police (PSP), the national police force of Portugal. GOE was created in 1982 and has around 200 operatives. Although a police unit, the GOE is employed worldwide, similar to the French GIGN or to the German GSG 9.
The Brigade Speciale Beveiligingsopdrachten (BSB) is the elite police tactical unit of the Royal Netherlands Marechaussee. Its missions include counter-terrorism, protection of government and military officials, and targeting organised crime.
Counterterrorism Special Detachment 88, or Densus 88, is an Indonesian National Police counter-terrorism squad formed on 30 June 2003, after the 2002 Bali bombings. It is funded, equipped, and trained by the United States through the Diplomatic Security Service's Antiterrorism Assistance Program and Australia.
The Counter-terrorism Rapid Response, formed in 1983, is a special police unit of Italy's Guardia di Finanza. It is tasked with counter-terrorism operations and the protection of VIPs and places of interest in the country. The ATPI has also participated in operations in Albania, Kosovo, and Hungary.
Mobile Security Deployments (MSD) is a small specialized tactical unit within the Diplomatic Security Service (DSS) of the United States Department of State. The MSD provides U.S. embassies and consulates with security support, protects the Secretary of State and other U.S. officials, including domestically as well as visiting foreign officials, and also provides security training at U.S embassies and consulates.
The Special Detective Unit (SDU) is the main domestic security agency of the Garda Síochána, the national police force of Ireland, under the aegis of the Crime & Security Branch (CSB). It is the primary counter-terrorism and counter-espionage investigative unit within the state. The Special Detective Unit superseded the Special Branch, which itself replaced the older Criminal Investigation Department (CID), which was founded in 1921. They work in conjunction with the Defence Forces Directorate of Military Intelligence (J2) – Ireland's national intelligence service – on internal matters. The unit's headquarters are in Harcourt Street, Dublin City.
The Protection Command is one of the commands within the Specialist Operations directorate of London's Metropolitan Police Service. The command specialises in protective security and has two branches: Royalty and Specialist Protection (RaSP), providing protection to the royal family and close protection to government officials, and Parliamentary and Diplomatic Protection (PaDP), providing uniformed security to government buildings, officials and diplomats. In contrast with the vast majority of British police officers, many members of the Protection Command routinely carry firearms in the course of their duties and all are authorised firearms officers.
The White House Police Force was a security police force formed in 1922 to protect the White House and the President of the United States. It became part of the United States Secret Service in 1930. It was renamed the Executive Protective Service in 1970 and then the Uniformed Division of the Secret Service in 1977.
Arintaraj 26 is the tier 1 police tactical unit of the Royal Thai Police (RTP).
The Rendőrség is the national civil law enforcement agency of Hungary and is governed by the Interior Ministry. It was formerly established under the Hungarian People's Republic in 1955, formally known as the Magyar Népköztársaság Rendőrsége.
The Directorate General of Security and Presidential Protection (DGSPP) is a close protection unit, administratively attached to the Algerian Republican Guard. It is responsible for the personal and immediate protection of the President of the Algerian Republic and his family.
The Missions Abroad and Special Operations is a specialized unit within the German Federal Criminal Police Office (BKA). The ASE is composed of specially selected and trained BKA personnel that typically operate in high-threat environments.
U.S. Secret Service 
