This article provides a comprehensive review of the State of the Art, regarding abuse of persons with disabilities as of 2/90. It provides a unique approach to defining abuse, gives statistics on incidence and prevalence, and a national review of data collection efforts. Prevention programs nationwide are scattered, and inconsistent, but represent a growing interest and implementation. Identification of abuse continues to be an obstacle, both for social service and law enforcement, who require information (date, location, perpetrator identification) that many developmentally disabled persons are unable to give. Recommendations for specialized requirements and interview approaches are given. Treatment issues include getting someone to make a referral to a clinician, then having a competent clinician available who is trained in the three areas of developmental disability, sexuality, and abuse treatment. Recommendations include training for direct service staff, development of SCAN teams at service sites, and improvement of social and legal systems to address the special needs of this population.