How much do children's early experiences affect their cognitive and social development? How important is the parent's role in child development? Is it possible to ameliorate or reverse the consequences of early developmental deficits? This study draws on research from the social sciences and studies on the brain to answer these questions and to explore what they mean for social policy and child and family development. The authors affirm that sound social policy providing for safe and appropriate early care, education, health care and parent support is critical not only for the optimal development of children, but also for strengthening families, communities and the nation as a whole. Offering a wealth of advice and recommendations, they explain: the benefits of family leave, child care, and home visitation programmes; the damage that child abuse inflicts; the vital importance of nutrition (and breast feeding) for pregnant women and young children; and the adverse effects that occur in misguided efforts to disseminate research too early.