Incest victims between 1 and 4 years of age often present with loss of toilet training, sleep disturbances, fear of men, or excessive clinging to the mother. They may indicate having been 'bothered' sexually; vulvar reddening may be the only physical evidence. Brief (two to eight sessions) play therapy and a physical examination are necessary for young children, who should be allowed to return home if parents agree to intensive therapy. Preschool children feel guilty about incest and react by warming to the perpetrator and withdrawing from the mother. Marital therapy is important here as mothers tend to be angry at either the husband or the daughter, or both. Latency age victims (9 to 12 years old), the most common incest group, are often reluctant to discuss sexual topics and may react by talking brazenly about the incest. A detailed history of school activities and hobbies is needed. These children should enter therapy with their siblings and should talk with other females. Depression is common. In adolescents, running away, promiscuity, or suicide are common. Adolescents want to explore the sexual details of the incest and their feelings toward the perpetrator. A sizeable portion of female psychiatric outpatients have experienced incest. They present with suicidal depression or with sexual problems. Many women fear they will abuse their own children or that a relative will sexually abuse their children as they had been abused. Group therapy for adults should focus on the traumatic experience, dispelling guilt, and clarifying moments in current situations when the woman responds as she did in the incest situation. Data indicate that preschool incest victims are at greater risk of later problems (i.e., depression, child abuse). Nine case examples and 17 reference are supplied.