The available information on the brain drain, its consequences and the professions most affected is insufficient to make sweeping generalisations. The area most affected by high emigration rates of the highly educated population is sub‐Saharan Africa. The
potential costs can be great: brain drain means loss of skills for the source country, loss of ideas and innovation, loss of the nation's investment in education and loss of tax revenues, but most importantly, perhaps, the loss of critical services
in the health and education sectors. "Brain overflow" in receiving countries can lead to misuse and subsequent downgrading of professional skills of migrants. There are other costs of emigration borne by sending countries: among them social effects which can create
regional inequalities, and strains on families and gender roles, children and their schooling, and crime.