Although child abuse has existed from prehistoric times, it was not recognized as a serious medical and social problem until the 1950's. The definition of child abuse in the Federal Child Abuse Prevention and Treatment Act of 1974 encompasses physical, emotional, and sexual abuse as well as neglect. According to data obtained from the National Study on Child Neglect and Abuse Reporting, an estimated 1,726,649 children were reported to child protective service agencies in 1984, an increase of nearly 17 percent over the previous year. About 42 percent of the reported cases were substantiated. The families involved tended to be poor, larger than average, and headed by a single female. Although physicians in all States are required by statute to report suspected cases, compliance is sporadic. Diagnosis includes history taking covering parental, situational, and child factors and physical examination that focuses on skin manifestations, bone injuries, other injuries, observations, and mistaken 'evidence.' Recidivism is high in child abuse, and there are long range effects. There is currently no sure 'cure' for child abuse. Removal of a child from an abusive environment can be life-saving, but subsequent care of the child is problematic. Family rehabilitation is the most promising approach, but costs obstruct such treatment. Identification and intervention are the most promising preventive approaches. In the future, ways must be found to reduce domestic violence and to supply the resources required for prevention and treatment. 47 references.