Methods of treating developmental disorders such as Angelman syndrome, Fragile X syndrome, Fragile X-associated tremor/ataxia syndrome (FXTAS), Autistic Spectrum Disorder, Autism, Asperger's syndrome, pervasive developmental disorder, Childhood Disintegrative Disorder, Rett syndrome, Lanau-Kleffner Syndrome, Prader-Willi Syndrome, Tardive Dyskinesia, and/or Williams Syndrome with gaboxadol or a pharmaceutically acceptable salt thereof are provided. The methods provide therapeutic compositions that may be used to improve one or more symptoms of the developmental disorder.
