The movement of migrants from developing and transition economies to OECD countries has created concerns about liberalising the provision of services and movements of people. Migration figures must be seen in context in order to inform policy making. Most migration in the OECD takes place between OECD countries themselves, even as mobility among developing countries is considerable. The extent of irregular migration is often exaggerated and today’s migration is overshadowed by 19th century migration to America from Europe. Mobility of the low skilled reduces poverty in the source country more readily than that of the highly skilled; the low skilled come from middle-income countries whereas mobility of the highly skilled affects low-income countries disproportionately. A new OECD database provides the basis for more systematic study of origins and skill levels of migrants in the OECD.