Policymakers, child care providers, and parents face tradeoffs in determining how much to spend on child care, including how many hours to purchase, and the features of programs that might influence quality. Given these tradeoffs, it is useful to understand what constitutes quality, the cost of care features associated with quality, the effects of quality on child development, and the links between policies, program features, and quality. To address these issues this report reviews more than 60 studies of infant and toddler child care conducted since 1985. The report concludes with a summary of key policy relevant findings, limitations of the research for informing policy, and recommendations for filling in knowledge gaps. [This publication is a product of the Infant and Toddler Policy Research Center at NIEER, which is within the National Institute for Early Education Research (NIEER) at the Rutgers Graduate School of Education.]