Photo by Angencia Brazil

Nidaa Hassan is a Syrian journalist who, under pseudonym, offers the Guardian the profiles of the prominent opponents in the Country.

Suhair Atassi, 30s, longtime pro-democracy activist, Damascus

After Atassi's Jamal Atassi Forum, which called for political reforms, was shut down in 2006, she shifted it to Facebook. She has repeatedly held – or tried to hold – pro-democracy protests. She has been threatened, beaten and arrested several times, most recently in March during a sit-in calling for the release of political prisoners. She is part of a core of Syrian activists, including other women such as Razan Zeitouneh, who are tweeting and sending information to the media.

Burhan Ghalioun, 65, professor of political sociology at the Sorbonne, Paris

One of Syria's respected intellectuals in exile, the academic Ghalioun has become a very public face of the uprising through numerous television and radio interviews. The author of 20 works, including The Arab Malaise, he is known for his strong opinions expressed in a calm, logical manner. He insists the leadership must come from the young people on the ground, but they require the outside help of people such as himself to keep media attention.

Radwan Ziadeh, 35, US-based head of the Damascus Centre for Human Rights

Ziadeh is a human rights lobbyist, author of 13 books and visiting scholar at George Washington University in the US, where he fled to in 2007 after being threatened with arrest. He has been monitoring deaths and human rights abuses during the protests, including in his home town of Daraya close to Damascus. He has tried, with limited success, to bring the opposition and activists together through a new alliance, the National Initiative for Change.

Adnan Mohamed, 40s, emerging leader in the besieged southern city of Deraa

An engineer whose brother, a doctor and father of six, was killed in the Omari mosque shooting on 23 March in Deraa. Mohamed, with others, has helped to organise protests, form a local committee and take care of families in the town with the highest death toll. He is believed to be a good negotiator and has been among those reportedly lobbying Ba'ath party members to resign – more than 200 party members and two legislators have done so.

Michael Kilo, 69, Christian writer and veteran political activist

Kilo divided opinion in Syria after writing an article in Lebanese newspaper As-Safir in April calling for a "political solution" to the crisis rather than revolutionary change, yet many see him as someone who could help navigate a peaceful end. From Latakia, Kilo is a well-respected Christian figure who has played a prominent role in Syria's modern history and in calling for reform. He was released in 2009 after spending three years in jail for signing the Beirut-Damascus Declaration in 2006 calling for the normalisation of relations between Syria and Lebanon and the end to Syrian dominance of its tiny neighbour.