This concise, yet practical handbook will aid in supporting the diagnosis, treatment, and long-term management of autism, including behavioral therapies, current clinical trials, and emerging pharmaceutical treatments. Autism spectrum disorder (ASD) is a developmental disorder characterised by disturbance in language, perception, and social skills that affects an estimated 1–2 per 1,000 people worldwide (although the number is as high as 20 per 1000 in the US). While studies have suggested a disturbance in neural metabolism in patients with ADS, the exact cause of the ASD still remains unknown. In 2013, a single indication of ASD, which united several related conditions (ie, classical autism, Asperger's syndrome, Fragile X Syndrome, Landau-Kleffner Syndrome, Rett syndrome, childhood disintegrative disorder, and PDD-NOS), was included in the fifth edition of the Diagnostic and Statistical Manual of Mood Disorders for the first time in order to support more standardized diagnoses.