This new edition revisits the major issues affecting individuals with mental retardation, those personally responsible for their education and well being, and society at large. The text provides up-to-date material on the major dimensions of the disorder - its nature, its causes, and its treatment or management. New topics covered include causation, diagnosis, and treatment of severe maladaptive behaviour disorders observed in mental retardation, including problematic sexual behaviours, and behaviour that is classifiable in terms of formal psychiatric syndromes. In addition, the revised text includes discussion questions at the end of each chapter, and boxed material and appendixes to supplement the content.