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.
United Nations Security Council Resolution 1646
The Security Council decided that the five permanent members of the Security Council–China, France, Russia, the United Kingdom and United States–and two non-permanent members were to participate in the Organisational Committee of the Peacebuilding Commission. Furthermore, the resolution stated that the annual report of the Peacebuilding Commission would also be submitted to the Council for debate.