The party or coalition commanding the support of a majority of the members of the Legislative Assembly is invited by the governor to form government.

[2] Currently, the Legislative Council has 36 members elected for four-year terms from multi-member constituencies by proportional representation, and the Legislative Assembly has 59 members, elected for four-year terms from single-member constituencies, using preferential voting.

In 1870 the then colony was ruled by a governor and an advisory Legislative Council made up of appointed officials and elected members.

The Western Australian Legislative Assembly was created in 1890 when the then colony attained self-government.

On 3 November 2011, the government introduced fixed four-year terms for Parliament, with elections being held every four years on the second Saturday in March.