Concern about the international migration of skilled human resources has traditionally focused on migratory flows to industrialized countries, i.e., about what has come to be known as the "brain drain". There are, however, migratory movements of this segment of the labour force within the region as well. This "horizontal" migration is analysed briefly in the present article; in so doing, the author reviews its causes, possible implications, the characteristics of these flows of skilled migrants, and the relationship between what is to be observed in some countries and the official attitude adopted by their Governments. This examination suggests that the emigration of skilled human resources, regardless of their destination, is invariably a loss for developing countries owing to these resources' high social value and economic cost. The author concludes that the subject calls for in-depth research at the intraregional level.