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.
P5+1
The P5+1 refers to the UN Security Council's five permanent members (the P5); namely China, France, Russia, the United Kingdom, and the United States; plus Germany. The P5+1 is often referred to as the E3+3 by European countries. It is a group of six world powers which, in 2006, joined together in diplomatic efforts with Iran with regard to its nuclear program.