The United Nations System consists of the United Nations, and the six principal organs of the United Nations: the General Assembly, Security Council, Economic and Social Council (ECOSOC), Trusteeship Council, International Court of Justice (ICJ), and the UN Secretariat,specialized agencies, and affiliated organizations.The executive heads of some of the United Nations System organizations and the World Trade Organization, which is not formally part of the United Nations System, have seats on the United Nations System Chief Executives' Board for Coordination (CEB). This body, chaired by the Secretary-General of the United Nations, meets twice a year to co-ordinate the work of the organizations of the United Nations System.

The United Nations System includes the United Nations and its subsidiary bodies (such as the separately-administered funds and programmes, research and training institutes, and other subsidiary entities), specialized agencies, and affiliated organizations. Some of the organizations of the United Nations System predate the founding of the United Nations in 1945 and were inherited after the dissolution of the League of Nations.

（编辑：三点水白）