A new OECD (Organisation for Economic Cooperation and Development) publication, entitled “A Profile of Immigrant Populations in the 21st Century”, presents some of the most comprehensive information currently available on the origin and structural characteristics of the immigrant population in OECD countries. The information is covered in nine thematic chapters, such as the gender dimension of brain drain, the international migration of health experts, or the role of low-skilled foreign-born workers in domestic services.