The
Fourth International (
FI), founded in 1938, is a
Trotskyist international. In 1963, following a ten-year schism, the majorities of the two public factions of the
Fourth International, the
International Secretariat and the
International Committee, reunited, electing a United Secretariat of the Fourth International. In 2003, the United Secretariat was replaced by an Executive Bureau and an International Committee, although some other Trotskyists still refer to the organisation as the USFI or USec.