Under the 1981 constitution, the president of the republic was elected by universal adult suffrage. The sole candidate was the president of UPRONA, the only legal political party. The president, who was head of state, was assisted by a council of ministers. Legislative power was vested in the 65-member National Assembly, of which 52 were elected and 13 appointed by the president. The president and legislators served five-year terms. Following the September 1987 coup, President Pierre Buyoya dismissed all members of the government and ruled as head of the newly established Military Committee of National Redemption until it was disbanded in December 1990. A new constitution, which recognized "democracy, human rights and development", was adopted on 13 March 1992 after a popular referendum. It provides for a directly elected president, a prime minister, and an 81-seat National Assembly.
In 2001, the National Assembly was expanded from 121 to approximately 140 seats under the transitional government. Members are elected by popular vote to serve five-year terms. There is also a senate with 54 seats and undefined lengths of term. The current senators will likely serve out the three-year transition period. The three-year transitional government, which handed power from Buyoyo to Domitien Ndayizeye at mid-term, was scheduled to end with national elections in late 2004.