This proposal is submitted in response to an NICHD RFA to assemble a cooperative agreement among a group of PI's to study the effects of infant child care, proposed is a longitudinal study of infant child care, such that its impact on child outcomes will be studied from the perspective of the social ecology of the family (i.e., parental values and attitudes, parental stress parental support, parent-child interactions, and family demographics), the social ecology of the child care setting (i.e., type of care, stability of care, quality of care, provider values, provider-child interactions, and provider stress and support), and individual differences among children (i.e., sex, temperament). Outcome variables in this site-specific proposal include attachment, behavioral-emotional problems, verbal intelligence, and language performance. Parent-child interaction and provider-child interaction will be measured with a newly-developed time budget survey to assess the life conditions of children in two settings, the home and the child care setting. Children (n=200), their parents, and their child care providers will be studied over a 39 month period, when the children range in age from 4 to 42 months. Children will be sampled randomly and identified through birth records to increase the generalizability of the results and because so many children attend unlicensed child care facilities. Families will be stratified by type of child care during recruitment (family day care vs. no child care), SES, and mother's age. The specific aims of the research are: (1) to examine the differences and similarities between the life conditions of infants in child care and infants not in child care; (2) to examine the relationship between the type of care infants receive and their concurrent and long-term development; (3) to examine the relationship between the quality of care infants receive and their concurrent and long-term development; (4) to examine whether the social ecology of the home and child care settings mediate the impact of child care on development; and (5) to examine whether individual differences among children (e.g., sex and temperament) mediate the impact of infant child care on development.