"We will work towards a unified vision," Burhan Ghalioun, the former head of the main opposition group the Syrian National Council, told AFP shortly before the two-day gathering kicked off here.
The meeting brings together various opposition factions including a Kurdish group and representatives from several Arab and Western countries are also here to observe the proceedings.
"We're here to define a common position," said Bassma Qodmani, SNC head of foreign relations. "There are many more points of difference between us."
France is represented by its ambassador to Damascus, who was recalled in November in protest at the violencve amascus regime violence. The United States, Germany, Italy and Turkey also sent senior diplomats.
Friday's meeting comes ahead of a planned major conference organised by opposition groups in Cairo under the auspices of the Arab League, at a date to be announced.
The newly-elected head of the SNC, Kurdish activist Abdel Basset Sayda, said as he took office last Sunday that his priority was to unify the opposition.
Monitors say more than 14,400 people, mostly civilians, have been killed in Syria since anti-regime protests erupted in March 2011, prompting a bloody crackdown by President Bashar al-Assad's forces.