This collection looks at fertility differentials and social inequalities across different groupings and across time. It contains twelve empirical papers that deal with both international migrants and internal migrants, both women and men, both older migrant populations spanning several generations as well as recent immigrant groups, such as refugees and include analyses of both behavior and intentions. The collection demonstrates the large heterogeneity in fertility among migrant and ethnic minority groups. Social inequalities shape fertility differentials, which in turn influence subsequent life-courses of migrants and ethnic minority group members.