Results presented in this paper based on the new database on immigrants and expatriates in OECD countries, show that (i) the percentage of the foreign-born in European OECD countries is generally higher than the percentage of foreigners; (ii) international migration is quite selective towards highly skilled migrants; (iii) in most OECD countries, the number of immigrants with tertiary education exceeds the number of highly qualified expatriates to other OECD countries; (iv) among non-member countries the impact of the international mobility of the highly skilled is diverse: the largest developing countries seem not be significantly affected and indeed may benefit from indirect effects associated with this mobility while some of the smallest countries, especially in the Caribbean and in Africa, face significant ‘emigration rates’ of their elites.