There are three chief reasons why people pursue child development. The first reason is grounded in a concern for an individual. The second is motivated by a class of people. The third is driven by the pursuit of abstract knowledge. The first two are based on practical concerns and the third on a quest for knowledge. This chapter discusses new research on imitation, joint visual attention, and emotion. It shows that infants are carefully watching our actions and imitating what they see. It focuses on the overturning of one of the most pervasive myths in social science—the myth of the asocial infant. Interpersonal imitation does not exhaust infant social cognition. An important aspect of social cognition is the realization that people are sources of information about external objects. Social cognition can be learned by observing third party interactions not involving the self. Children learn by watching how siblings interact and observe their parental relationship.