This paper presents a theoretical model of empathy in which empathy is defined as a largely involuntary vicarious response to affective cues from another person or from his situation. The model has three components: affective, cognitive, and motivational. In the presentation of the affective component, five distinct models of empathic affect arousal are discussed in their approximate order of appearance developmentally. The discussion of the cognitive component includes a review of the development of the sense of other. In the presentation of the motivation component, the research on empathy and prosocial behavior is summarized. (JMB)