This article introduces a special issue on childhood and migration. It argues that understandings of the ways in which children form belongings and attachments are enhanced by conducting research with children who migrate or who live mobile and transnational lives. The articles in this collection highlight the mobile and translocal nature of children's lives, from different perspectives and in different global and migration contexts. Taken together, they make a number of key contributions to an emerging literature on the lives of migrant, mobile and diasporic children and young people. They emphasize the situated and contextualized nature of migrant children's negotiations of home and belonging. In particular, the collection explores children's and young people's constructions of home and belonging, often negotiated in contradictory or challenging circumstances and frequently destabilizing powerful assumptions about the nature of migration, mobility and childhood, such as ideals of childhood based on notions of residential fixity.