The period from birth to three years lays important foundations for development and life-long learning and increasing attention has been paid to child development during these very early years. Findings from research on Early Childhood Care and Education (ECCE) should ideally be transformed into policies and practices which facilitate child development. However, despite compelling research findings which stress the importance of the psychological and physical environment for early human development, policy makers have given less attention and allocated fewer resources to promote the development of the under-threes compared to those for older children. This brief considers research relevant to the development of under-threes and its implications for policy making for this age group. (author abstract)