Outgoing president: Hamid Karzai
Hamid Karzai has been president since the Taliban was overthrown in 2001 and will soon be replaced because he has served the two consecutive terms permitted by the constitution.
Eleven candidates competed in the presidential elections on 5 April 2014.
The major contenders are former foreign minister Abdullah Abdullah, former finance minister Ashraf Ghani Ahmadzai, former foreign minister Zalmay Rasul, former anti-Soviet guerrilla leader Abdorrab Rasul Sayyaf, and former Nangarhar Province governor Gol Agha Sherzoi.
Mr Karzai won a second five-year term in an August 2009 election widely criticised as marred by fraud.
Hundreds of thousands of votes were declared invalid, cutting Mr Karzai's share of the vote to under 50%. A second round was avoided when his main opponent withdrew, saying not enough had been done to prevent further fraud.
During his second term, Mr Karzai has admitted that his government and its Western allies have failed to bring peace to Afghanistan. He has called for firm aid commitments from international donors after the planned departure of Nato-led combat forces in 2014.
Ahead of the pull-out, his rhetoric has been increasingly critical of foreign forces, in what observers see as an effort to dissociate himself from his Western backers.
The president has acknowledged chronic corruption and pledged to tackle the problem.National unity
Hamid Karzai was initially put in charge of the provisional administration set up when the Taliban were driven from power in 2001, and won Afghanistan's first direct presidential elections in October 2004.
He faced the tough challenges of forging national unity, disarming regional militias and tackling drug production.
Mr Karzai, a Pashtun leader, was seen an effective player on the world stage and initially he enjoyed strong backing from his Western allies.
However, the president's relations with the West cooled amid allegations of corruption in his administration.
Mr Karzai has defended the presence of international troops in Afghanistan, but criticised the heavy civilian casualties caused by civilian casualties.
When the Afghan army took formal command of all military and security operations from Nato forces in June 2013, the president declared an end to air strikes.
From 2008-11 Mr Karzai held secret reconciliation talks with Taliban factions, with the knowledge and cooperation of the US, but dropped them as futile.
In early 2013 he and Pakistan's President Asif Ali Zardari agree to work for an Afghan peace deal within six months after talks hosted by Britain's Prime Minister David Cameron.
President Karzai announced that he would hold direct talks with the Taliban again in the summer, but expressed anger at US plans to to do the same on the grounds that they would compromise the government's efforts.
Born in the southern town of Kandahar in 1957, Hamid Karzai studied in India and France. He was exiled in Pakistan for much of the Soviet occupation and during Taliban rule.