Millions of children are on the move, both within and between countries, with or without their parents. The conditions under which movement takes place are often treacherous, putting migrant children, especially unaccompanied and separated children, at an increased risk of economic or sexual exploitation, abuse, neglect and violence. Policy responses to protect and support these migrant children are often fragmented and inconsistent and while children on the move have become a recognised part of today’s global and mixed migration flows they are still largely invisible in debates on both child protection and migration.