SIPTU (; ''Services, Industrial, Professional and Technical Union''; ) is Ireland's largest trade union, with around 200,000 members. Most of these members are in the Republic of Ireland, although the union does have a Northern Ireland District Committee. Its head office, Liberty Hall, is in Dublin, and the union has five industrial divisions, three in the private sector and two in the public sector. SIPTU is affiliated to the Irish Congress of Trade Unions Provided by Wikipedia