The Developmental Disabilities and Bill of Rights Act defines a developmentally disabled child as one who is physically or mentally impaired, manifests the disability before 22 years of age, and is likely to be affected indefinitely. The Child Abuse Prevention and Treatment Act defines child abuse and neglect as the physical or mental injury, sexual abuse, or exploitation of a child. Definitional issues, however, limit an accurate assessment of the prevalence of abuse, not only in children with disabilities but also in the general population. One study indicates the incidence of maltreatment of children with disabilities is 1.7 times greater than for children without disabilities. Other studies exploring the prevalence and type of abuse perpetrated against children with disabilities report conflicting data and highlight difficulties in the diagnosis of abuse in children with disabilities. The vulnerability of disabled children to physical abuse and sexual assault is addressed in terms of child factors, parental factors, interactional factors, and theoretical models. Treatment and prevention program approaches are described, areas for further research are suggested, and public policy recommendations are offered. 63 references