Brain drain from developing to developed countries is far from a clear win. Here's some good links talking about the effect of emigration of Kenyan health care workers (mostly to the UK and the US) on Kenya: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1538589/ https://assets.aspeninstitute.org/content/uploads/files/cont...

Half of Kenyan-trained doctors live and work outside of Kenya. That represents a multi-million dollar direct cost just in the governmental and societal resources used to train those doctors, and a much larger cost to society of the limited health care infrastructure thanks to a loss of so many workers.