Estonia has a multi-party system, with several political parties representing a range of ideologies. The main parties include the Estonian Reform Party, which is center-right and focuses on free market policies, and the Centre Party, which appeals primarily to the Russian-speaking population and emphasizes social welfare. Other notable parties are the Social Democratic Party and the Conservative People's Party of Estonia. Elections in Estonia are held every four years, and the political landscape can shift significantly between elections. The Riigikogu, Estonia's parliament, consists of 101 members elected through a proportional representation system, allowing smaller parties to gain representation alongside larger ones.