Mauritanians are due to elect a new president on 18 July after 11 months of military rule. The military postponed the poll from 8 June because of a threatened opposition boycott, which was avoided by an agreement at talks in Dakar, Senegal.
What was the Dakar agreement?
The agreement reached at talks in Senegal on 26 June ended months of street protests by the National Front for the Defence of Democracy (FNDD) opposition coalition. It provided for the formal resignation of President Mohamed Ould Cheikh Abdellahi, who was ousted in a military coup in August 2008, and the formation of an independent electoral commission.
Who can stand?
Front-runner Gen Abdelaziz led the 2008 coup
Any Mauritanian citizen can stand for the presidency, expect for those serving in the military or who have a criminal record. They must also be Mauritanian-born, Muslim and aged 40-75.
Under amendments to the Constitution in 2006, the president is directly elected for a five-year term. The president is restricted to two consecutive terms - the only such provision in the Arab world.
Who is standing?
Mohamed Ould Abdelaziz. The general who ousted President Abdellahi in 2008 is now standing for president as leader of the new Union for the Republic party, which 83 out of 151 members of parliament have joined. He has campaigned on a platform of fighting poverty and corruption.
Ahmed Ould Daddah is a veteran opposition leader
Ahmed Ould Daddah. The leader of the main opposition Rally for Democratic Forces (RFD), Mr Ould Daddah is the strongest challenger to Mr Abdelaziz. A half-brother of the country's first president and a senior official in the 1960s and 1970s, Mr Ould Daddah lost the 2007 election run-off to President Abdellahi. Allied with the FNDD, he also enjoys the support of major business and political figures in the country.
Who else is standing?
Ibrahima Moctar Sarr. A journalist and leader of the Alliance for Justice and Democracy/Movement for Renovation (AJD-MR), Mr Sarr ran for the presidency in 2007 on a platform of equal rights for his fellow black Mauritanians. A supporter of the 2008 coup, he was prepared to stand in the postponed June presidential elections this year.
Messaoud Ould Boulkheir. A veteran left-winger, current speaker of parliament and prominent opponent of Mr Abdelaziz, Mr Boulkheir leads the People's Progressive Alliance (APP). He has agreed to back Mr Ould Daddah in a second round.
Kane Hamidou Baba. A long-standing member of the RFD and current deputy speaker of parliament, Mr Hamidou Baba split with Ahmed Ould Daddah over the 2008 coup.
Mohamed Jamil Ould Mansour. Leader of the National Rally for Reform and Development, Mr Mansour is the first Islamist to stand for president. His group broke local Islamist tradition and joined the FNDD coalition.
Also standing are: Ely Ould Mohamed Vall, the leader of the 2005-2007 military regime; Salah Ould Mamadou Ould Hanan, a member of Mr Abdelaziz's government; and Hamadi Ould Meimou, the former head of the Anti-Poverty Commission.
Who can vote?
All Mauritanian citizens aged 18 and above can vote, as long as they have identity cards and are on the electoral register. A supplementary census began in February to register refugees returning from Senegal. Expatriates will also be allowed to vote under new provisions.
How is the winner decided?
If no candidate wins an absolute majority of votes cast on 18 July, the two leading candidates go through to a second round on 1 August.
Is media coverage fair?
All candidates appear to have full access to state and private media. Mohamed Ould Abdelaziz has threatened to boycott the Al-Jazeera pan-Arab satellite TV channel over alleged bias in favour of Ahmed Ould Daddah, which the channel has denied. The FNDD had earlier complained that Al-Jazeera coverage was biased against it.
Is the election expected to be fair?
International observers deemed the 2007 presidential election to have been free and fair. Observers from the African Union, France, Spain, the International Francophonie Organisation, the Arab Maghreb Union, the Arab League and the Community of Sahel and Sahara Countries (Comessa) have confirmed that they will attend.
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