Children feature prominently in migration, fertility and mortality studies and are evident in those more broadly-based geographies which consider the importance of population to socio-economic and environmental issues. However, it is argued that the population geography of childhood is a mirage, in that children are ever-present, but never really there. Trends toward the pursuit of`peopled' population geographies and the emergence of a (social) geography of childhood provide contexts within which new population geographies involving children can emerge. Such geography holds out the prospect of enriching our understanding of population patterns and processes. To realise this goal necessitates a theoretical engagement with children and childhood.