Robert J. Fletcher, DSW, ACSW, is the founder and CEO of the National Association for the Dually Diagnosed and has more than 35 years of clinical experience in providing individual, group, and family psychotherapy for persons with a dual diagnosis. He is the author or editor of several books in the field, including Therapy Approaches for Persons with Mental Retardation, and is the chief editor of the Diagnostic Manual?Intellectual Disability. He lives in Kingston, New York. Steven Reiss, PhD, is a professor of psychology at the Ohio State University,the director of the Nisonger Center for Mental Retardation and Development Disabilities, and the author of The Normal Personality. He lives in Columbus, Ohio.