The Government meets once every three months. Between meetings it is guided by a standing Council of Ministers which meets at least weekly. The Council of Ministers includes the Prime Minister, the Deputy Prime Minister, and some Ministers, chosen by the Prime Minister among the heads of Ministries. The Deputy Prime Minister and Ministers belonging to Council of Minister are nominated by the premier, and appointed by the Emperor with House of Peers' approval. The Prime Minister is nominated and appointed by the Emperor. Each ministry supervises one sector. Commissions are outranked by ministries and set policies for and coordinate the related activities of different administrative organs. Offices deal with matters of ongoing concern. Also bureaus and administrations rank below ministries,