Sao Tome and Principe profile
President: Manuel Pinto da Costa
Former strongman Manuel Pinto da Costa returned to power in elections in 2011, two decades after losing office.
Mr Pinto da Costa ruled Sao Tome with an iron fist for 15 years after independence from Portugal in 1975, and observers warned his return to power could herald a slide towards authoritarianism.
He lost the presidency after introducing reforms in 1990, including multi-party democracy that saw the election as president of Miguel Trovoada.
Mr Pinto da Costa has a five-year mandate. He worked with Prime Minister Patrice Trovoada whose Democratic Action party won legislative elections in 2012. However, the president dismissed Mr Trovoada and his government in December 2012 following a no-confidence vote in parliament.
Under the democratic constitution adopted in 1990, the president shares power with a government headed by a prime minister, who needs the confidence of parliament to stay in power.
In October 2014, the opposition ADI party won parliamentary elections with an outright majority. Led by ex-prime minister Patrice Trovoada, the ADI won 33 of the 55 seats.