Służba Bezpieczeństwa Ministerstwa Spraw Wewnętrznych (Security Service of the Ministry of Internal Affairs) was established in 1956 and was the most important security organisation in the Polish People’s Republic.

Prior to Security Service, the Ministry of Public Security (MBP) was responsible for all intelligence and counter-intelligence actions. However, it was known for harsh methods in pursuing opposition against the newly established communist power and dismantled in 1954.

Służba Bezpieczeństwa’s role was clearly defined: to protect the Polish People’s Republic from internal and external enemies which was achieved through controlling almost every aspect of citizens’ life. Therefore, throughout the decades, the SB gathered enormous number of files on Polish society.