United Nations Security Council
Along with the five permanent members, the Security Council of the United Nations has temporary members that hold their seats on a rotating basis by geographic region. Non-permanent members may be involved in global security briefings. In its first two decades, the Security Council had six non-permanent members, the first of which were Australia, Brazil, Egypt, Mexico, the Netherlands, and Poland. In 1965, the number of non-permanent members was expanded to ten.
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.