This essay supports William Kessen's recent call for a reorientation of child development research toward studies of the child in context and focuses on problems in monocultural studies of the child to argue that this reorientation will require significant changes in child development research methodology. Research on cultural differences in moral reasoning patterns and infant sleeping behavior is used to argue that a disregard for the role of cultural context in describing the child can lead to a lack of differentiation between the structure of the child's own development and the structure of the environment. Cultural differences in infant motor development are employed to show that when research focuses on only one culture, individual differences in infants are more obvious than differences in contexts and the effects of culture are rendered invisible. The fact that researchers are often members of the culture studied is said to have a similar effect and to encourage the development of genetic or universalistic theories, even of group differences (e.g., IQ) within cultures. It is suggested that what is needed is not merely more cross-cultural studies but also new theories of development produced by the collaboration of anthropologists and psychologists. (Author/BH)