It is estimated that 7.2 million people in the United States have mental retardation or associated impairments - a spectrum now referred to as intellectual disability. This book provides professionals with the latest and most reliable information on these disabilities. It utilizes a developmental perspective and reviews the various types of intellectual disabilities, discusses approaches to classification, diagnosis, and appropriate interventions, and provides information on resources that may offer additional help. Case examples are included in each section to highlight specific diagnostic and treatment issues. The emphasis in this book is on the development of the person, the provision of interventions for behavioral and emotional problems associated with intellectual disability, and the positive support necessary for self-determination. It discusses the facilitation of transitions throughout the lifespan from infancy to maturity and old age. Additionally, the book reviews evaluations for behavioral and emotional problems, genetic factors, appropriate psychosocial, medical, and pharmacological interventions, and family and community support.