The largest trade union federation in the world is the Brussels-based International Trade Union Confederation (ITUC), which has approximately 309 affiliated organizations in 156 countries and territories, with a combined membership of 166 million.
National and regional trade unions organizing in specific industry sectors or occupational groups also form global union federations, such as Union Network International, the International Transport Workers Federation, the International Federation of Journalists, the International Arts and Entertainment Alliance or Public Services International.