This article proposes an estimation of international migration to the six main receiving countries of the OECD between 1975 and 2000. The analysis reveals a large increase in international migration during this period, together with a substantial change in migrant skills. In parallel with this phenomenon we note a significant rise in skill levels at world level. An analysis by country shows a high degree of stability in the list of the countries most affected by the brain drain. While overall change in the migration of skills is limited, the list of countries with the largest losses of highly skilled workers in 1975 is largely unchanged twenty-five years later.