The South Australian Parliament is based on the British Westminster system of Parliamentary Government. The Government is formed by the party or grouping having the majority of the seats in the House of Assembly, or by a coalition (the combination of parties to form a majority).
South Australia operates under responsible Cabinet Government: the Governor acts on the advice of the Ministers (i.e. the Cabinet), headed by the Premier.
The Ministers each are in charge of government departments; and they are Members of Parliament on the Government side of the Chamber which is to the right-hand side of the Speaker. Every Minister is also a member of the Executive Council. The Executive Council is presided over by the Governor, and is the formal executive arm of the Government giving legal force to certain Cabinet decisions, appointments and similar matters. These and other provisions are established by convention.
The South Australian Cabinet consists of fifteen Ministers who may be Members of the House of Assembly or the Legislative Council. The functions of Cabinet include the final determination of the policy to be submitted to Parliament.
Policy matters are discussed in Cabinet and a decision is taken. The decision then becomes binding on every member of the Cabinet, who must defend it even if they did not agree with it and were out numbered in the Cabinet vote. If they do not agree to defend the decision, or to take responsibility, they must resign. This unwritten convention of Cabinet Government derives from the Westminster system.
The Cabinet also has control of the public service.