Child health is a major indicator of the direction and well-being of society. It is a significant factor predicting health and productivity in adult life, and the health of adults in turn affects the well-being of the next generation of children. The most important outstanding issues include determining the most cost-effective investments in child health, explaining the relationship between health and socio-economic status over the life course, and finding the interventions that are most effective in breaking the inter-generational cycle of ill health and poverty. As children are economic actors in their own right, their well-being is worthy of study.