The newest edition of the most comprehensive handbook on autism and related disorders Since the original edition was first published more than a quarter of a century ago, The Handbook of Autism and Pervasive Developmental Disorders, Volume 1: Diagnosis, Development, and Brain Mechanisms, has been the most influential reference work in the field of autism and related conditions. The new, updated Fourth Edition takes into account the changes in the disorders' definitions in the DSM-V and ICD-10 that may have profound implications for diagnosis and, by extension, access to services. Along with providing practical clinical advice--including the role of psychopharmacology in treatment--the handbook codifies the ever-expanding current body of research throughout both volumes , offering a wealth of information on the epidemiology of autism and the genetic, environmental, biochemical, social, and neuropathological aspects of the disorder. Volume 1 includes: Information on outcomes in adults with autism spectrum disorders * A range of issues and interventions important from infancy, though adolescence and beyond for individuals with autism spectrum disorders * Current information about play development, including skills, object play, and interventions * Coverage of the state of genetic, biochemical, and neuropathological autism research * Chapters on psychopharmacology and medical care in autism and related conditions The new edition includes the relevant updates to help readers stay abreast of the state of this rapidly evolving field and gives them a guide to separate the wheat from the chaff as information about autism proliferates.