The first conference addressing the global shortage of health workers is opening in Kampala.
The World Health Organization says a further four million doctors, nurses, midwives and other health care professionals are needed.
The WHO says the shortage is affecting basic services such as immunisation, child birth and treatment of diseases.
There is a critical shortage of health workers in 57 countries, most of which are in Africa.
Medical staff from Africa and Asia often migrate to richer countries where pay and conditions are better.
On average, one in four doctors trained in Africa is working in the developed world.
The conference, which is being attended by health ministers from some of the worst affected countries, aims to produce a global action plan.
No lack of money
The WHO says there is a need for more education and training to create a larger pool of health workers.
But there are also calls for improved management of the migration of health professionals.
The BBC's Sarah Grainger in Kampala says the issue seems to be more concerned with organisational problems rather than a lack of funds.
Some $12bn in international aid is devoted every year to health.
The WHO wants to see a quarter of that spent on the workforce, rather than drugs or treatments.
The brain drain, and the best way to retain talent, is a hot topic of debate across Africa.
Thousands of Africans move abroad each year to earn more money and attain a higher standard of living.
The UK and the US are the preferred destinations.
In 2003, 5,880 UK work permits were approved for medical personnel from South Africa, 2,825 from Zimbabwe, 1,510 from Nigeria and 850 from Ghana.
