Diplomats had talked up the importance of getting the two sides in the same room in Geneva, but at one point things were so bad that it looked like that room might be the departure lounge at the city's airport.
But meet in the conference chamber they did, cajoled by o
"If this conference fails then the situation will explode regionally," said one diplomatic source, like others speaking on condition of anonymity because of the delicate negotiations.
U.N. mediator Lakhdar Brahimi began by focusing on a deal on humanitarian access to the besieged and starving city of Homs before steering the talks towards the highly contentious question of a political settlement of a war that has killed 130,000 and forced millions to flee their homes.
While both sides are ready to discuss a 2012 document which called for political transition, their interpretations of it are wildly divergent. The opposition say it means President Bashar al-Assad must step aside while the government says calls for his departure are the stuff of fantasy.
Diplomats said that to square that kind of circle, they will have to keep the talks going for months or perhaps even years.
The hope is that over time the membership of delegations will evolve, with the opposition becoming more representative of the people doing the fighting and the government side reflecting a reappearance of doubts about Assad's durability.
"The longer the talks last, the more likely different opponents will join the process," said the diplomatic source. Other sources said if the Geneva process takes off, support for Assad on the government side of the table may weaken.
But opposition unity is at least as fragile and will be sorely tested if the talks drag on without result. The continued acquiescence in the negotiations shown by some rebel groups in Syria can also not be taken for granted, and al Qaeda-linked fighters reject them outright.
In the meantime, delegates sat in silence on opposite wings of a U-shaped table as Brahimi set out his agenda. And when the heads of delegation spoke, it was to Brahimi not to each other.
The painstaking stage management, designed to keep friction to a minimum and restrain mutual hatred, was part of a finely tuned diplomatic effort to lock the sides into talks.
"It's just the nature of this, that it could stall or explode any day," said a Western diplomat after the first face-to-face meeting in the high-ceilinged, wood-paneled room on the 5th floor of the United Nations European headquarters in Geneva.
He said, only half-joking, that the room in a sealed-off section of the labyrinthine U.N. complex was selected specifically for its inaccessibility - out of reach of journalists, diplomats and other potential interference.
Those practical preparations were matched by the patient diplomacy of Brahimi himself in the months leading up to the talks as he, along with the United States and Russia, pushed the wary parties towards the negotiating process.
"Expectations are low so we'll see how things develop day by day. Every day that they talk is a little step forward," another diplomatic source in Geneva said on the eve of talks which the opposition only formally agreed to just over a week ago.
While Western and other nations backing the opposition met its chief negotiator every evening to discuss strategy and calm nerves, diplomats said they were looking to Russia, Assad's major ally, to press the government side to let aid into Homs. Other proposals included local ceasefires and prisoner swaps.
"They (the Russians) want this process to succeed, but this will be a test for them on how much sway they really have on the regime," the diplomatic source said.
BACK FROM THE BRINK
Aware of the enormous challenge of finding common political ground in the middle of a civil war, Brahimi avoided diving straight into the most divisive issue - the future of Assad.
The 80-year-old veteran of conflict resolution has never portrayed himself as a man in a hurry. "I didn't say going slow is great. I am saying be careful, don't run before you can walk," he told journalists.
Brahimi's strategy does appear to have tied the two sides into the negotiations just a few days after they came to the brink of disaster.
On Friday, both threatened to pull out - the opposition refusing to talk until the government signed up to the 2012 Geneva accord on Syria, and the government warning it would return to Damascus unless the talks started the next day.
Those threats have subsided, replaced by a qualified readiness to engage in political issues which Brahimi says form the core of his mission - albeit from largely irreconcilable positions and laced with acrimonious public exchanges.
"I am happy because in general there is mutual respect and they are aware of the fact that this attempt is very important and must continue," he said.
SITTING WITH THE ENEMY
Sitting down with their opponents in the sparsely furnished negotiating room - complete with translators' cubicles in the corner for Brahimi's non-Arabic speaking staff - has not been easy. Delegates from each side make no effort to hide the disdain they feel for their opponents.
The last time 83-year-old Haitham al-Maleh looked across a table to a representative of Assad's government was when he was being interrogated, he said. The former judge served a total of 10 years in prison on charges which included "weakening national morale".
"I kept looking at them one by one," Maleh said of the government delegation. "I have spent a long time in jail and I have seen this regime kill and torture its people. But I still don't understand how anyone could defend it".
At the official start of the talks on Friday, activists Rima Fleihan and Suhair al-Atassi carried pictures of Abdelaziz al-Khayyer, a veteran dissident who was abducted in Damascus two years ago and whose fate remains unknown.
"The regime needs at least to feel shame," Fleihan said.
For the government, sitting down for talks with people it has blamed for inciting bloodshed has also been a challenge.
"We sit across the table because we love our country," presidential adviser Bouthaina Shaaban said as she arrived one morning at the United Nations from the lakeside Hotel de la Paix (Peace Hotel) where the government delegates are staying.
"We are here because we don't want to leave a door unopened if we can help our people and put an end to this terrorism and put an end to this horrible war," she said.
Asked to describe the mood at the first meeting, Shaaban said: "No tension. Calm and logical talks."
Brahimi characterized the first sessions as a civilized discussion and a "good beginning", a message reinforced by diplomats who described the talks as free from drama.
The opposition's Western and Gulf Arab backers hope that the longer the talks last - especially if they start to bear fruit - the more chance the opposition has of winning support from rebels who remain either suspicious or openly hostile to the talks and owe no allegiance to the political exiles.
But the opposition, aware that that strategy could backfire and that prolonged talks could simply harden the hostility of rebels and Syrian civilians, has told the West it will not get sucked into a stagnant process which resembles the decades-old Palestinian-Israeli negotiations.
For now in Geneva, though, few people's horizon extends beyond the immediate days ahead. "I can't tell you where this is going," the Western envoy said. "But there were a lot of people who said this will collapse on day one. And it hasn't."
BY DOMINIC EVANS AND KHALED YACOUB OWEIS