In power since succeeding his father 2000, Bashar al-Assad is fighting for control of his country after protests against his rule turned into a full-scale armed rebellion.
He inherited a tightly controlled and repressive political structure from long-time dictator Hafez al-Assad, with an inner circle dominated by members of the Assad family's minority Alawite Shia community.
But cracks began to appear in early 2011, in the wake of the "Arab Spring" wave of popular dissent that swept across North Africa and the Middle East.
Following successful uprisings against authoritarian rulers in Egypt and Tunisia, pro-democracy demonstrations were held in Damascus and several other cities.
President Assad responded with a mixture of concessions - dismissed as superficial and disingenuous by the opposition - along with a brutal crackdown, accusing his opponents of being "terrorists" funded by enemies abroad. But the attempts at repression - as well as attempts at international mediation - failed and the conflict turned into a fully-fledged internal war.
Mr Assad's government continues to enjoy strong diplomatic support from Russia and traditional ally Iran, while some even accuse these powers of supplying it with arms. The president's troops have been bolstered by fighters from Lebanon's Iranian-backed Hezbollah militant group.
Rise to power
Bashar al-Assad would probably have been working as an optician had his brother not died in a car accident in 1994.
The death of Basil - groomed to succeed Hafez al-Assad - catapulted the younger brother into politics, and into the presidency after his father died in June 2000.
During his six-year political apprenticeship, Bashar al-Assad completed his military training, met Arab and other leaders and got to know the movers and shakers in Syrian politics.
On taking office he ushered in a brief period of openness and cautious reform. Political prisoners were released and restrictions on the media were eased. Political debate was tolerated and open calls for freedom of expression and political pluralism were made.
But the pace of change alarmed the establishment - the army, the Baath party and the Alawite minority. Fearing instability and perceiving a threat to their influence, they acted not only to slow it down, but to revert to the old ways.
A referendum in 2007 endorsed Bashar al-Assad as president for a second seven-year term. He was the only candidate.