In contrast to previous reviews that have dealt extensively with either situational determinants of intervention in emergencies or norms governing prosocial actions, the present paper focuses primarily on the role of empathy and sympathy in mediating helpful acts. To provide a meaningful context in which to integrate research in this area, two distinct tasks are undertaken. First, the conceptual meaning of altruism is discussed via a comparison of general definitions of this term and an examination of its evolutionary and behavioral aspects. Second, empirical findings implicating the role of empathy and sympathy in facilitating prosocial behaviors are reviewed comprehensively. A synthesis of these relevant findings is attempted via discussions of (1) the nature of altruistic motivation, (2) the development of a capacity to relate emotionally to others, and (3) the processes involved in learning the value and form of altruistic behaviors. (Author)