This study is a 10-site cooperative agreement to examine the effects of non-maternal care, especially during the first year of life. It focuses on the social and intellectual development of children in an ecological framework which takes into account the complex interactions of non- maternal care experiences with home and family conditions, parenting practices, and child characteristics. Over 1200 families were enrolled in the study during 1991. These families will participate in the study for 36 months. The Data Coordinating Center (DCC) is responsible for data management and protocol monitoring. It serves as the focal point for receipt of collected data and for data processing.