The Main-d'œuvre immigrée was a French trade unionist organisation, composed of immigrant workers of the Confédération générale du travail unitaire (CGTU) in the 1920s.
During the Second World War, Louis Grojnowski (called "Brunot") and Simon Cukier aka Alfred Grant took charge, and the organisation gave rise to an armed squad, the FTP-MOI, directed by Joseph Epstein.
After the mass arrest of more than 13,000 Jews in the Vel' d'Hiv Roundup in July 1942, the groups became somewhat more active.
Pursued relentlessly by the Special Brigades of the Renseignements généraux, almost all the MOI fighters had been identified by the end of summer 1943.
In Belgium too there was a Main-d'œuvre immigrée organization, which took part in the Belgian Resistance in the ranks of the Front de l'Indépendance under the leadership of the Bulgarian Todor Angelov and the Italian-Belgian Jacques Grippa, while others were also active in Solidarité juive or in the Comité de Défense des Juifs, led by Hertz Jospa and Have Groisman.