Africa's growth record in the post-colonial era has been an "economic tragedy," according to a report from the World Economic Forum.
Delegates are gathering in Maputo, Mozambique
In a damning assessment of the continent's economy, the report says income per head has fallen by 11% in sub-Saharan Africa since 1974.
"The long-awaited revival of the African economy has not yet taken place," it concludes.
The report was unveiled at an economic summit in Mozambique's capital, Maputo.
It looked set to overshadow the conference, aimed at taking stock of an ambitious plan to revitalise the African economy.
The plan - dubbed the New Partnership for Africa's Development, or Nepad - commits African nations to improving financial accountability and raising governance standards in order to boost investment from rich countries.
The WEF report ranked Botswana top out of 25 African countries in terms of competitiveness, crediting the quality of its political institutions and its stable macroeconomic environment.
Tunisia was in second place, followed by South Africa, while Chad came bottom of the league.
WEF chief economist August Lopez-Claros acknowledged that the report's findings were not encouraging, but stressed that they could be used to draw up solutions to Africa's problems.
"African countries do not, on the whole, perform well in this study," he said.
"It is difficult to pinpoint a single group of African economies that have experienced high, sustained per capita income growth.
"However, (the study identifies) those areas where policy reforms are vitally needed if Africa is to fulfil its potential."
The Maputo conference, attended by leaders including South African president Thabo Mbeki, comes amid doubts over whether Nepad is working.
Last week, South African media reports suggested that no private sector cash had so far been invested in a series of Nepad-sponsored infrastructure projects.
Companies' alleged reluctance to back the projects comes despite a strong show of support from the private sector when Nepad was launched two years ago.
The meeting will also scrutinise the World Economic Forum's latest annual snapshot of 25 leading African economies.