The Security Council is organized to function continuously and to meet as often as necessary. Hence, a representative from each member state must always be available so that in an emergency the council can convene at once. Chairmanship rotates among the council's member states according to their English alphabetical order, a new president (as the chairman is called) presiding every month. It is up to the president to decide whether to preside during the discussion of a question that directly concerns his own country.
Council members normally are represented by the heads of their permanent missions to the UN, who have the rank of ambassador. Any state that is not currently a council member but is a party to a dispute under consideration by the council must be invited to send representatives to participate in the proceedings, though without the right to vote. (In these circumstances, the disputing states concerned usually send a high government official, very often the foreign minister.) When the council is discussing a matter other than an actual dispute, the decision to invite the participation of any UN member states whose interests are directly affected is left to its discretion. The council has usually acceded to requests for such invitations. It has also granted representatives of national liberation organizations the opportunity to speak at a number of meetings.
The Security Council has held sessions away from its New York headquarters on two occasions, in Addis Ababa, Ethiopia, in 1972, to consider questions relating to Africa, and in Panama City, Panama, in 1973, to consider questions relating to Latin America.