Fourth International

A Trotskyist political international that was founded in 1963.

Following a ten-year schism, in 1963 the majorities of the two public factions of the Fourth International, the International Secretariat of the Fourth International (ISFI) and the International Committee of the Fourth International (ICFI) reunited.

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.