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 Regional Groups
The Western European and Others Group (WEOG for short) has 28 members (15% of all UN members). It has a territory dispersed on all of the continents, but mostly centred in Western Europe and North America. In addition, the United States is an observer (see below). Including the United States, WEOG has 5 seats on the Security Council: three permanent seats (France, United Kingdom, United States), and two non-permanent seats. The Group also has 13 seats on the United Nations Economic and Social Council and 7 seats on the United Nations Human Rights Council. In the rotation of the post of the President of the United Nations General Assembly, the group is eligible for having its nationals elected to this post in years ending with 0 and 5; most recently, Mogens Lykketoft of Denmark was elected to this position in 2015.