Book excerpt: This book provides a comprehensive overview of the diagnosis, management and treatment of the psychiatric comorbidities encountered in adolescents and adults with Autism Spectrum Disorder (ASD). After discussing key issues in diagnosing ASD in adolescents and adults, the opening part of the book examines the genetics, neuroimaging and neuropsychology of ASD. Several chapters are then devoted to all of the psychiatric comorbidities such as psychosis, obsessive-compulsive disorder, depression, bipolar disorder, anxiety disorders, eating disorders etc. For each disorder, the clinical symptoms, biological basis, diagnostic criteria and treatment options are described in detail. In addition, a special chapter is devoted to people with intellectual disabilities. Thanks to its clear approach, Psychopathology in Adolescents and Adults with Autism Spectrum Disorders will be an invaluable resource for psychiatrists, psychologists and neuropsychiatrists, as well as allied mental health professionals, caring for these patients.