Around the world, nearly 50 million children have migrated across borders or been forcibly displaced – and this is a conservative estimate. More than half of these girls and boys fled violence and insecurity – 28 million in total. Children in these contexts are among the most vulnerable people and this vulnerability is only getting worse. The number of child refugees under the United Nations High Commissioner for Refugees’ (UNHCR) mandate has more than doubled in just 10 years. Migrating and displaced children are at risk of some of the worst forms of abuse and harm. Often dependent on human smuggling, they can easily fall victim to traffickers and other criminals. Many are subjected to extreme forms of abuse and deprivation during their journeys. This report presents, for the first time, comprehensive, global data about these children – where they are born, where they move, and some of the dangers they face along the way. The report sheds light on the truly global nature of childhood migration and displacement, highlighting the major challenges faced by child migrants and refugees in every region.