Paul Biya has been in power since 1982
Cameroonians choose a new president on 11 October in an election which sees the incumbent Paul Biya pitted against a divided opposition. Many doubt if the vote can be fair, saying the result will be announced by a ministry rather than an independent body. BBC Monitoring looks at the background.
Q: What is at stake?
President Biya won 93% of the vote in the last election in 1997, when the opposition staged a boycott over the short campaign period and alleged bias by the electoral commission.
This time he again delayed announcing the election date, giving his 15 opponents just 30 days - the minimum required - to campaign. Doubts over the independence of election supervisors have been raised.
The president's supporters say he has managed to maintain political stability in a region wracked by violence. He has vowed to safeguard peace and to revive the economy.
Despite its oil riches and a growth rate above most African countries, Cameroon remains poor. Diplomats and donors have blamed this on corruption and economic mismanagement - themes seized on by the opposition.
Human rights are also an issue, in the wake of a recent crackdown on opposition demos and the killing of a prominent opposition official.
Concerns have been raised over the president's health, his numerous foreign trips and a border row with Nigeria over the oil-rich Bakassi Peninsula.
And there have been street protests in the capital Yaounde, calling for electoral reform, particular of voter registration.
Q: Who can stand?
Candidates must be over 35 and have resided in the country for 12 consecutive months prior to the election. They must not hold any other elected post.
One candidate, Jean-Jacques Ekindi, has launched a legal challenge against Mr Biya, saying he holds two posts: Cameroonian president and chairman of a political party.
Mr Ekindi says President Biya should step down as chairman of the ruling party.
Q: Who are the main candidates?
President Paul Biya, 71, is standing for the ruling Cameroon People's Democratic Movement (RDPC). The party has ruled since independence in 1960.
A Sorbonne-trained lawyer, he has been in power for 22 years, first as prime minister then president.
He says he is seeking re-election in response to public calls for him to stand. Veteran footballer Roger Milla has campaigned on his behalf.
The RDPC, founded in 1945 as the Cameroon National Union (UNC), remains the most popular party, with support in the Christian-dominated central, southern and eastern regions.
Adamu Ndam Njoya, candidate of the 11-party Coalition for National Reconciliation and Reconstruction (CNRR), is President Biya's main rival.
The opposition coalition was founded in 2003 by disaffected former ministers, rights activists and veteran opposition leaders.
Mr Njoya is a Muslim, who heads the Cameroon Democratic Union (UDC). His party has support in the Muslim-dominated northern regions, where 20% of the country's 16m people live.
Mr Fru Ndi has strong support in English-speaking areas
John Fru Ndi, 63, is the candidate of the Social Democratic Front (SDF), which he chairs.
He withdrew from the opposition coalition after refusing to acknowledge Mr Njoya's leadership, and launched his own presidential bid.
Mr Ndi comes from the English-speaking northwestern Cameroon, where he enjoys widespread support. English-speaking Cameroonians constitute 20% of the population.
Q: Who else is running?
Other candidates include:
Victorin Hameni Bieuleu of the Union of Cameroon Democratic Forces (UFDC); Fritz Pierre Ngo of the Cameroonian Ecologists Movement (MEC); Yondo Mandengue Black of the Social Movement for the New Democracy (MSND); Dominique Djeukam Tchameni of the Movement for Democracy and Independence (MDI). Mr Tchameni has the support of 10 smaller opposition parties.
Q: What is the system?
Under the constitution elections must be held between 14 September and 14 October.
The president is elected for seven years and, following a 1996 amendment, can only serve two terms.
The process is supervised by the National Elections Observatory (Onel) and the results are announced by the Ministry of Territorial Administration and Decentralisation.
Voting is in a single round, with the candidate with most votes declared the winner.
Voters must be over 20 and possess a national identity card. Eligible voters must confirm their name in the register. They collect registration cards 15 days before polling day.
Q: What's the problem with registration?
Opposition supporters want the voters' register to be computerised. The ministry overseeing elections says it cannot afford the 17m dollars required.
A Commonwealth team who monitored registration in some towns reported irregularities, which the government has denied.
The team said the legal and operational framework of the registration process was "unsatisfactory".
People in rural areas have complained they have not received their cards. The opposition says the issuing of cards favours Biya supporters.
The election commission said in September that 4.3m people had registered. The opposition and foreign diplomats say the figure should be higher, at about 8m voters in this country of 16m inhabitants.
The opposition has also called for the deployment of more election supervisors and the use of transparent ballot boxes.
The UK and Japan have donated 25,000 transparent ballot boxes to be distributed to the country's 23,000 polling stations. South Korea has donated 40 computers.
Q: Will there be monitors?
There has been no firm announcement in Cameroon about foreign observers. However, the EU, UN, the Commonwealth and la Francophonie, the group of French-speaking nations, have reportedly offered to send monitors.
The local Citizens Committee for Electoral Transparency, headed by Achille Kotto, will also try to ensure fair play. The organisation monitored the 2002 parliamentary election.
Q: What of the media?
Communications Minister Jacques Fame Ndongo has issued guidelines on how candidates use the media.
He said the measures are to "create maximum conditions for transparency and equity". And he urged the media to "respect the rules of decency, public morals and public order".
He cautioned against incitement to violence and publishing reports that could undermine the country's unity and territorial integrity.
BBC Monitoring, based in Caversham in southern England, selects and translates information from radio, television, press, news agencies and the Internet from 150 countries in more than 70 languages.