Syndicalism is a revolutionary current within the labour movement that, through industrial unionism, seeks to unionize workers according to industry and advance their demands through strikes and other forms of direct action, with the eventual goal of gaining control over the means of production and the economy at large through social ownership.
Syndicalist unions first emerged in Spain and North America in the 1870s, before rising to prominence in France and later emerging on other continents. Syndicalist movements were most predominant amongst the socialist movement during the interwar period that preceded the outbreak of World War II. Major syndicalist organizations included the General Confederation of Labor (CGT) in France, the Confederacion Nacional del Trabajo (CNT) in Spain, the Italian Syndicalist Union (USI), the Free Workers' Union of Germany (FAUD), and the Argentine Regional Workers' Federation (FORA). Although they did not regard themselves as syndicalists, the Industrial Workers of the World (IWW) (nicknamed "Wobblies") in the United States, the Irish Transport and General Workers' Union (ITGWU), and the Canadian One Big Union (OBU) are considered by most historians to belong to this current.
The International Workers' Association – Asociación Internacional de los Trabajadores (IWA–AIT), which was formed in 1922, is an international syndicalist federation of various labour unions from different countries. At its peak, it represented millions of workers and competed directly for the hearts and minds of the working class with social democratic unions and parties. A number of syndicalist organizations were and still are to this day linked in the IWA–AIT; some of its member organizations left for the International Confederation of Labour (ICL–CIT), which was formed in 2018.