World Bulletin / News Desk
The international talks in Vienna on Syria's conflict are expected to include discussion of which members of the fragmented opposition will attend any final negotiations on a peace deal.
Here are some of the main groups operating inside Syria and abroad:
Opposition in exile
National Coalition: The leading opposition grouping in exile, created in Doha in November 2012.
The group includes members from across the political and ethnic spectrum and represents some military forces, though it is often accused of being removed from the realities on the battlefield.
It has been recognised by 120 countries as the representative of the Syrian people and participated in two rounds of peace talks in Geneva with regime delegates in 2013 and 2014.
The Coalition believes the war must be resolved along the lines of a document produced by the so-called Geneva I conference among leading powers in 2012.
It called for a transitional government with full executive powers, which the Coalition says means President Bashar al-Assad must step down.
It is currently headed by Khaled Khoja, and is based in Turkey.
Cairo Conference: Formed in January 2015, the grouping brings together some 150 domestic and exiled opposition figures, including Kurds. One of the group's co-founders is Haytham Manaa, a longtime dissident.
The grouping was represented in talks in Moscow and presents itself as an alternative to the National Coalition, though it has not been recognised as such.
Muslim Brotherhood: The powerful group is banned in Syria but remains a prominent member of the opposition.
It belongs to the National Coalition, but has its own backers, including countries including Turkey.
The group dates back to the 1930s and led an uprising in Syria that was brutally crushed by then-president Hafez al-Assad in 1982.
Independent figures: There are also a variety of high-profile independent Syrian opposition figures overseas who have been mentioned as potential parties to any negotiations.
National Coordination Committee for Democratic Change (NCCDC): Founded in 2011, the group includes leftist, nationalist and Kurdish parties as well as individual dissidents.
From the beginning of the conflict, it declared its opposition to any foreign intervention in Syria.
The group is generally tolerated, but its members have been regularly harassed and detained by regime forces throughout the conflict.
It participated in talks organised by Moscow on the conflict in 2014 and 2015.
Popular Front for Change and Liberation: a coalition of parties established in 2011 and led by Qadri Jamil, a former deputy prime minister who was fired in 2013.
He now lives in Moscow and has good relations with the Russian government.
Another of the group's key figures is Fateh Jamous, a former head of the Communist Labor party, who was imprisoned by the regime for 20 years, but continues to live in Syria.
Building the Syrian State party: Founded in 2011 and led by Louay Hussein, a prominent activist from the same minority Alawite sect as the president.
He was arrested in Damascus in 2014 and accused of "weakening national sentiment." Freed in May, he fled to Madrid. His party is opposed to the use of violence.
Figures close to the regime: There are several individuals who present themselves as part of the Syrian opposition but participate in the current government.
Among them is Ali Haidar, the current minister of national reconciliation and head of a branch of the Syrian Social Nationalist Party, who participated in talks in Moscow on the war.
Others include members of several parties created after a multi-party law was passed in 2011, some of whom were invited to peace talks in Moscow.
Democratic Union Party (PYD): Founded in 2003, this is the leading Syrian Kurdish party. It effectively governs a semi-autonomous region in parts of north and northeast Syria.
The group does not belong to the National Coalition, but has participated in the Cairo Conference.
The PYD's armed wing, the Kurdish People's Protection Units, has been a leading opponent of the ISIL group and a key ally of the US-led coalition fighting the rebels.
Turkey considers both to be branches of the banned Kurdistan Workers Party (PKK).
Kurdish National Council: A coalition of smaller Kurdish parties that does not include the PYD. Formed in 2011, it participates in the National Coalition, though it differs with the grouping on the issue of Kurdish autonomy.
Güncelleme Tarihi: 14 Kasım 2015, 10:47