Here is a major new work on human infancy written by one of the country's leading developmental psychologists and two distinguished colleagues. At its core is the long-awaited report of the authors' six-year study of infant daycare. Important in its own right, this experiment becomes the occasion for a wide-ranging discussion of cognitive and emotional processes in infancy, of the effects of early experience on later growth, and of the deep-seated cultural and historical assumptions that underlie our views of human development. For those concerned with social policy, the book provides the best empirical assessment now available of the effects of group care on the psychological well-being of infants. It also supplies a blueprint for quality daycare that may well stand as a model for future nurseries. For those interested in the course of cognitive and emotional development, the book provides rich information about the major growth functions that characterize human infancy. It also outlines an explanation of these growth functions that links changes in emotional behavior to the maturation of underlying cognitive processes in a new and provocative way. And for everyone interested in human nature, the book of offers a controversial thesis about the discontinuity of psychological growth that challenges some of our most fundamental assumptions about the nature of individual development.