One distal, cognitive component of parenting is knowledge of infant development. This multifaceted construct includes knowledge of developmental norms, parental skills, and abstract principles of development. Generally, it has been assumed that knowledge of development affects childrearing practices; this assumption is documented in various bodies of literature and is evident in parent-education programs. Acquisition of parental knowledge may occur through exposure to sociocultural sources of information (such as the advice of experts, family, and friends) or through direct observation of infants and children. Research conducted with 256 mothers of 6-month-old infants indicates that books, the family doctor, and the parents' social network are the most important sources of information. Furthermore, such sociocultural influences appear to shape knowledge more powerfully than do direct, observational experiences with children. Research also suggests that more knowledgeable mothers rate their infants as having easier temperaments and that knowledge of development influences the way parents structure interactions between children and the social and physical environment. Presently, little is known about parents' experiences, knowledge, beliefs, and perceptions. Future studies of parental knowledge should develop better measurement techniques; seek a more complete description of origins and variations in knowledge, beliefs, and perceptions; and work toward a coherent typology of cognitive influences on parental behavior. (RH)