16 December 2012 Last updated at 06:38 ET

Sao Tome and Principe profile

President: Manuel Pinto da Costa

Mr Pinto da Costa is serving his second, non-consecutive term in office

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.

Prime minister: Gabriel Arcanjo Ferreira da Costa

Gabriel Arcanjo Ferreira da Costa was appointed prime minister after the president dismissed Patrice Trovoada and his government in December 2012 following a no-confidence vote.

The assembly's second party MLSTP/PSD had nominated Mr Ferreira da Costa, a consensus builder from a political group without parliamentary representation.

Mr Ferreira da Costa had already briefly served as prime minister in 2002, a job held by 15 different people since 1990 and the installation of democracy.