United Nations System
There are 15 members of the Security Council, consisting of five veto-wielding permanent members (China, France, Russia, the United Kingdom, and the United States) and 10 elected non-permanent members with two-year terms. This basic structure is set out in Chapter V of the UN Charter. Security Council members must always be present at UN headquarters in New York so that the Security Council can meet at any time.
United Nations Security Council
Unlike the General Assembly, the Security Council meets year-round. Each Security Council member must have a representative available at UN Headquarters at all times in case an emergency meeting becomes necessary.