Security Service of Ukraine

The Security Service of Ukraine (Ukrainian: Служба безпеки України, romanized: Sluzhba bezpeky Ukrainy) or SBU (Ukrainian: СБУ) is the law enforcement authority and main intelligence and security agency of the Ukrainian government, in the areas of counter-intelligence activity and combating organized crime and terrorism. The Constitution of Ukraine defines the SBU as a military formation, and its staff are considered military personnel with ranks. It is subordinated directly under the authority of the president of Ukraine. The SBU also operates its own special forces unit, the Alpha Group.

The SBU is the successor of the Ukrainian branch of the Soviet KGB, created after the Declaration of Independence of Ukraine in 1991. The agency was viewed negatively by the Ukrainian public for much of its history, as it was widely regarded as corrupt and was best known for arresting and intimidating political dissidents. After the Revolution of Dignity in 2014, the SBU went through a restructuring with the transition to the new government, because of its corruption and possible infiltration by intelligence agencies of Russia.

The SBU has since been involved in operations against Russia, pro-Russian separatists in Donbas and other Russian sympathizers after the start of the war in Donbas and the wider Russo-Ukrainian War.