The Special Investigation Service or STT (Lithuanian: Specialiųjų tyrimų tarnyba) is a law enforcement institution in Lithuania serving under the Seimas and the President of Lithuania to combat corruption. With departments in Kaunas, Klaipėda, Šiauliai and Panevėžys, its objectives are to identify and investigate cases of corruption as well as to prevent it through education and introduction of improved procedures in the public sector.