The Syrian government and the country's largest mainstream opposition group have announced that they are sending delegations to Geneva, where peace talks are being hosted.
The embattled Syrian regime's delegation is headed by its ambassador to the UN, Bashar al-Jaafari, as well as a number of diplomats and lawyers.
Syrian Deputy Foreign Minister Faisal al-Moqdad will oversee the talks from Damascus.
And opposition figures from a Saudi-backed alliance of groups, including the National Coalition and several armed factions, have announced their delegation.
It will be headed by defected Syrian pilot Asaad al-Zoabi with Mohammed Alloush -- a senior official in the powerful Jaish al-Islam rebel group -- as chief negotiator.
Born in Damascus in 1956, Jaafari began his career in Syria's foreign ministry in 1980.
He served in multiple posts, including as Syria's representative in Geneva, until he was appointed as Syria's permanent representative to the United Nations in 2006.
Jaafari served as the regime's chief negotiator in the last round of peace talks in Geneva in early 2014 and headed a government delegation that later met with some opposition groups in Moscow.
In March 2014, US authorities informed Jaafari that he would be restricted to a 40 kilometre (25 mile) travel radius around New York city.
Jaafari has a doctorate in political science from the Sorbonne University in Paris. He is married to an Iranian woman and is fluent in Farsi, French, and English.
Syria's deputy foreign minister was born in 1954 in the south of the country.
He holds a doctorate in English literature.
Moqdad first ente red the diplomatic fold in 1994 and a year later he joined the Syria team at the UN mission in New York. In 2003, he became Syria's ambassador to the world body.
During the Vienna talks in October, Modqad, who rose the ranks to become deputy foreign minister in 2006, ruled out a transition period in Syria.
A source close to the government said that Moqdad will oversee the Geneva talks from Damascus, due to illness.
Asaad al-Zoabi was born in 1956 in southern Syria. He joined Syria's air force academy in 1974, then rose through the ranks to become a brigadier general.
He also worked as a military consultant in Yemen for more than two years.
Zoabi defected from the Syrian air force in August 2012 and fled to Jordan. From there, he began serving as a military adviser to rebel groups operating in the southern provinces of Daraa and Quneitra as well as Damascus.
He often appears on television programmes as a military analyst.
Mohammed Alloush was born in 1970 in Douma, now a rebel bastion in the opposition-held Eastern Ghouta area east of Damascus.
Alloush heads the political division of the powerful Jaish al-Islam (Army of Islam) rebel group.
He is the cousin of slain Jaish al-Islam head Zahran Alloush, killed in an air strike claimed by Syria's government on December 25.
Alloush studied Islamic law for one year in Damascus before moving to the Saudi city of Medina. In 2009, he received a degree in accounting in Beirut, according to a biography provided to AFP by Jaish al-Islam.
Jaish al-Islam, which is opposed to both the government and the Islamic State group, is believed to receive wide backing from Saudi Arabia.
Alloush is a former member of the Syrian National Council.