The House of Representatives (Thai: สภาผู้แทนราษฎร; rtgs: Sapha Phu Thaen Ratsadon) was the lower house of the National Assembly of Thailand, the legislative branch of the Thai government. The system of government of Thailand was that of a constitutional monarchy and a parliamentary democracy. The system of the Thai legislative branch was modeled after the Westminster system. The House of Representatives had 500 members, all of which are democratically elected: 375 members were directly elected through single constituency elections, while the other 125 are elected through party-list proportional representation. The roles and powers of the House of Representatives were enshrined in the Constitution of 2007.