Migration across multiple borders is a defining feature of the time in which we live, and children are central to this contemporary migration phenomenon. A core aim of this volume is to contribute at an empirical level to knowledge about the intersection between children, migration, and mobilities by highlighting underresearched child and youth short-term and micro movements within major migration fluxes that occur in response to migration and global change. This collection positions this complex mobility-in-migration within individual, intergenerational, and collective migratory lifespan trajectories. Drawing together empirical research from around the globe, we see how in the lives of children and young people, migration and mobility intersect so that migration is not an end state but rather is one form of movement in lives characterized by multiple journeys, short, circular or seasonal migrations, and holiday and pleasure mobilities that are dynamic and often ongoing into the future. However, left-behind children of transnational migrant parents experience physical immobility/imaginative mobility in circumstances in which restrictive migratory regimes in the receiving country make family reunification extremely difficult. Chapters use multi-sited and/or multi-temporal and virtual methodologies as researchers follow their research subjects over time and space.