The fragmented nature of existing data on child development prevents us from having a comprehensive, readily available picture of which children are affected by developmental problems, how many children are delayed, and what the extent of their problems is. Similarly, our understanding of the factors affecting children's development is limited. As a consequence, policies, programs, and clinical decisions are often formed with incomplete, if not erroneous, information. To serve a broad audience of policymakers, researchers, clinicians, and journalists, this project will produce a consolidated chartbook on the current status and trends of children's development in the United States and the factors that affect it. Researchers also will review the various sources of data and provide recommendations to strengthen future data collection. The chartbook will help the Fund call attention to deficiencies in children's development and inadequacies in services to address them, while at the same time promoting better quality and more collaborative research to improve develop-mental care.