The Socialist Labour Group was a Trotskyist group in Britain between 1979 and 1989.
The SLG originated politically in the 1971 split in the International Committee of the Fourth International (ICFI), between Gerry Healy's British Socialist Labour League (SLL) and Pierre Lambert's French Internationalist Communist Organisation (OCI). Betty Hamilton, an SLL founder and a Trotskyist since the 1930s, had sided with Lambert in 1971 but remained isolated, although still formally an SLL member until 1974. John and Mary Archer, also Trotskyists since the 1930s, had split with the SLL in the mid 1960s, disagreeing with its pullout from the Labour Party after 1964, with the exception of a few secret 'deep entrists'. They continued to work as individuals in the Labour Party in North London but for ten years were not active in an organisation. They were contacted in 1975 by Robin Blick (now a musician) and Mark Jenkins, (now a playwright in Wales) both leading SLL members who had broken with Healy in the early 1970s and formed a discussion circle centred on a critique of Healy which tended to see the SLL's move to become the Workers' Revolutionary Party (WRP) as similar to the Stalinist Third Period. Harry Vince (now an artist) and Ken Stratford had broken with the SLL in the late 1960s, arguing it was becoming a sect increasingly separated from the working class. They had joined and been expelled from International Socialists and Workers' Fight, discussed with the Militant and Chartists and were active in the Labour Party, forming a small group called Socialist Action. Regis Faugier (now a linguist) was a French ex-SLL member in St Helens who had organised a group of supporters outside the SLL, including Jean Faugier (now a nursing academic and consultant) Vince, Stratford and the Faugiers were in touch with the OCI from 1972 and in contact with Betty Hamilton from 1973.