A project led by the Manpower Demonstration Research Corporation (MDRC), in conjunction with collaborators from the University of Texas at Austin, examining the relationship between center- and home-based care settings and the development of low income children (primarily children of working parents), aged kindergarten to third grade. The research is based on two unique datasets: (1) a pooled dataset of seven experimental studies of welfare and employment programs--empirical techniques that take advantage of treatment-induced differences in employment, income and child care--that is used to control for child care selection factors; and (2) The National Institute of Child Health and Human Development Study of Early Child Care and Youth Development (NICHD SECCYD)--a longitudinal child care study following children from birth--that is used to conduct an analysis of features of different types of care settings and the resulting effects on children's development. This research addresses critical questions about the effects of center- and home-based care settings on multiple domains of low income children's development, paying specific attention to the direction of causality in effects.