There are currently 55 trade unions with membership of Congress, representing about 600,000 members in the Republic of Ireland. Trade union members represent 35.1% of the Republic's workforce. This is a significant decline since the 55.3% recorded in 1980 and the 38.5% reported in 2003. In the Republic, roughly 50% of union members are in the public sector. The ICTU represents trade unions in negotiations with employers and the government with regard to pay and working conditions
The supreme policy-making body of Congress is the Biennial Delegate Conference, to which affiliated unions send delegates. On a day-to-day basis Congress is run by an Executive Committee and a staffed secretariat headed up by the general secretary, Patricia King who succeeded David Begg in the position in 2015.
John Douglas of Mandate became President of Congress at the biennial conference in Belfast in July 2013 succeeding Eugene McGlone of Unite. The president serves for a two-year period and is succeeded by one of two vice-presidents.
Congress enjoyed unprecedented political and economic influence over the period from 1987 to 2009 under the umbrella of Ireland's social partnership arrangements. This involved a series of seven corporatist agreements with the government and the main manufacturing/services employer body IBEC and the construction employers' lobby, CIF (Construction Industry Federation). It was a classic European-style alliance of government, labour and capital built on six decades of voluntary employment relations regulated by state institutions such as the Labour Court.