Chairman of the General National Congress: Nuri Abu Sahmein
Libya's interim parliament elected Nuri Abu Sahmein as its chairman, and therefore de facto head of state, in June 2013, following the resignation of Mohamed al-Magarief.
Mr Al-Magarief had been elected to head the General National Congress a year earlier, but he stepped down when parliament approved a law debarring officials of the Gaddafi period from office. He had served as ambassador to India in the 1980s.
Mr Abu Sahmein is an independent MP from western Libya and, significantly, a member of the Berber ethnic minority that suffered discrimination under Col Gaddafi's rule.
The 200-seat Congress, elected in July 2012 in the country's first free polls in decades, saw liberal, secular and independent candidates outflank the Muslim-Brotherhood-aligned Justice and Construction Party.
Parliament chose Mr Abu Sahmein to serve as Libya's interim head of state pending fresh elections. These were originally due to be held towards the end of 2013, but are now not expected to take place before June 2014.
Interim Prime Minister: Abdullah Al-Thinni
Abdullah al-Thinni was named interim prime minister in March 2014 after the Libyan parliament or General National Congress dismissed Ali Zeidan from the post after declaring it no longer had confidence in him following the breaking of a Libyan navy blockade of a rebel-held port.
Mr Al-Thinni, who had previously served as defence minister, said on taking office that the biggest challenge facing the government was the security situation in Libya, and that the authorities would seek to bring peace and stability to the whole of the country. He also pledged to stop the export of oil from rebel-held ports.
Mr Zeidan had been struggling to maintain his authority ever since a separatist revolt against the central government in Tripoli broke out in July 2013.
The government had failed to regain control over large parts of the country after militants occupied three major eastern ports in August 2013 and demanded not only autonomy for the historic eastern region of Cyrenaica, but also a greater share of Libya's oil revenues.
Mr Zeidan was appointed prime minister by parliament in October 2012. His broad-based interim government - consisting of a mixture of liberal figures and Islamists, and aiming to strike a balance between Libya's various regions - was officially inaugurated in November 2012.
He served as a diplomat for Libya during the 1970s, but in 1980 defected together with his then boss - Libya's ambassador to India, Mohamed Magarief. Following his defection, he spent nearly three decades in exile in Geneva, where he worked as a human rights lawyer.
During the 2011 revolution against Col Gaddafi he served as the opposition National Transitional Council's European envoy, and is credited with winning the rebels recognition by several European countries.
Elected to the General National Congress as an independent in 2012, he beat the Muslim Brotherhood's Mohammed Harari to the premiership.
His interim government faced the challenge of uniting secular, regionalist and Islamic interests in support of a new constitution and parliamentary elections, but found itself unequal to this task after the armed groups and tribesmen who helped topple Muammar Gaddafi began to assert their own demands.