Malaysia is a federal constitutional elective monarchy. It is nominally headed by the Paramount Ruler or Yang di-Pertuan Agong, commonly referred to as the King of Malaysia. The Yang di-Pertuan Agong is selected for a five-year term among the nine hereditary Sultans of the Malay states; the other four states, which have titular Governors, do not participate in the selection. This makes Malaysia an elective monarchy.
The system of government in Malaysia is closely modeled on that of Westminster parliamentary system, a legacy of British colonial rule. In practice however, more power is vested in the executive branch of government than in the legislative, and the judiciary has been weakened by sustained attacks by the government during the Mahathir era. Since independence in 1957, Malaysia has been governed by a multi-racial coalition known as the Barisan Nasional (formerly the Alliance).
The bicameral parliament consists of the lower house, the House of Representatives or Dewan Rakyat (literally the "Chamber of the People") and the upper house, the Senate or Dewan Negara (literally the "Chamber of the Nation"). The 219-member House of Representatives are elected from single-member constituencies that are drawn based on population for a maximum term of 5 years. Legislative power is divided between federal and state legislatures. All 70 Senators sit for 3-year terms; 26 are elected by the 13 state assemblies, 2 representing the federal territory of Kuala Lumpur, 1 each from federal territories of Labuan and Putrajaya, and 40 are appointed by the king. Parliamentary elections are held at least once every five years, with the last general election being in March 2004. Registered voters of age 21 and above may vote for the members of the House of Representatives and in most of the states, the state legislative chamber as well. Voting is not compulsory.
Executive power is vested in the cabinet led by the prime minister; the Malaysian constitution stipulates that the prime minister must be a member of the lower house of parliament who, in the opinion of the Yang di-Pertuan Agong, commands a majority in parliament. The cabinet is chosen from among members of both houses of Parliament and is responsible to that body.
The state governments are led by chief ministers (Menteri Besar in Malay states or Ketua Menteri in states without hereditary rulers), selected by the state assemblies (Dewan Undangan Negeri) advising their respective sultans or governors.