The Republic of South Africa is a representative democracy with three-tier system of government and an independent judiciary, operating in a parliamentary system. Legislative authority is held by the Parliament of South Africa. Executive authority is vested in the President of South Africa who is head of state and head of government, and his Cabinet. The President is elected by the Parliament to serve a fixed term. South Africa's government differs greatly from those of other Commonwealth nations. The national, provincial and local levels of government all have legislative and executive authority in their own spheres, and are defined in the South African Constitution as "distinctive, interdependent and interrelated".
Operating at both national and provincial levels ("spheres") are advisory bodies drawn from South Africa's traditional leaders. It is a stated intention in the Constitution that the country be run on a system of co-operative governance.
The national government is composed of three inter-connected branches:
All bodies of the South African government are subject to the rule of the Constitution, which is the supreme law in South Africa.
The bicameral Parliament of South Africa makes up the legislative branch of the national government. It consists of the National Assembly (the lower house) and the National Council of Provinces (the upper house). The National Assembly consists of 400 members elected by popular vote using a system of party-list proportional representation. Half of the members are elected from parties' provincial lists and the other half from national lists.