Aung San Suu Kyi's opposition opened a historic conference on Friday seen as a key chance to revitalise the popular but inexperienced party, which faces major challenges ahead of elections in 2015.
The Nobel laureate's National League for Democracy (NLD), for years banned by a junta that lived in fear of its huge public support, has been urged to enlist the help of outside experts and inject new blood into its elderly top ranks.
Propelled by Suu Kyi's huge popularity, the NLD is widely expected to take power in the country also known as Burma if the next election is free and fair, capping a remarkable transition from military rule to democracy.
But some experts question whether the opposition is ready for the challenges of running the impoverished nation, which include building basic infrastructure, kick-starting the economy, redrawing the legal system and reviving poorly funded health and education sectors.
"It will be a litmus test for them, whether they are a party coming out of the darkness and proving they are worthy of leading this country," said one Burmese political analyst who asked to remain anonymous.
"The NLD will need to build capacity within the organisation if they become the next government. I don't think they have anyone capable of running this show," he added.
The NLD faces the financial and political might of President Thein Sein's Union Solidarity and Development Party (USDP), created by former generals who shed their uniforms to run for office in controversial elections held in 2010.
The USDP, which suffered a major drubbing at the hands of the NLD in by-elections held in April last year that saw Suu Kyi elected to parliament, is also searching for a new strategy to avert a major defeat.
An estimated 850 representatives will attend the three days of talks that aim to redefine the NLD leadership.
Red flags bearing the NLD peacock emblem were erected on a stage in a Yangon restaurant for the landmark congress while a large picture of Suu Kyi and her late father -- independence hero Aung San -- was erected outside.
NLD flags festooned the road to the entrance while arriving delegates wore party arm bands, another sight unthinkable until recently in a country that endured decades of iron-fisted junta rule until early 2011.
But it was unclear whether the party's maiden congress would bring sweeping change, and there was an air of secrecy on the first day with media refused permission to enter.
Many senior party members are in their 80s and 90s and have not said whether younger activists would be elevated into the upper ranks of the NLD at the congress to replace the elderly leaders, known as the "NLD uncles".
"New ideas are not solicited or encouraged from younger members, and the Uncles regularly expel members they believe are 'too active'," according to a leaked diplomatic cable from the US embassy in Yangon dated 2008.
Suu Kyi, 67, who spent 15 years locked up by the former junta, is expected to be comfortably reappointed as head of the party at the congress.
Delegates will also pick a 120-member Central Committee who will in turn elect a core executive of 15 people.
In a sign of tensions within the party, four members were banned from attending the congress, accused of trying to influence the voting ahead of the meeting.
"When this sort of thing happens at the grassroots, it could be bad for the leader and the party," said one of the accused, former political prisoner Khin Maung Shein, explaining that he had merely asked some NLD representatives in Yangon whether they wanted to be nominated to the Central Committee.
The congress is the latest sign of the dramatic changes seen since a quasi-civilian regime, led by former general Thein Sein, took power in 2011, ending years of isolation and heralding a flood of aid and investment.
Suu Kyi, who was due to attend on Saturday, has not ruled out ambitions of becoming president herself, but a constitutional rule now bars her from the role as she was married to a Briton and has two sons who are foreign nationals.