This part introduction presents an overview of the key concepts discussed in the subsequent chapters. The part describes in some detail how nursing !Xun mothers stimulate their young infants in ways that promote nursing, nutrition, and motoric development. It looks at the extent to which Bofi mothers let their toddlers decide when to wean themselves. The part focuses on that adult avoid interfering with their children's play. It addresses the affective quality of the relationships between children and others in their community. The part describes shifts from patterns of childcare to child development. It explains developmental issues in analysis of the circumstances that potentiate cooperative breeding and childcare. Cultural differences in explicit commitment to the exercise of social influence over young children are also apparent.