The National Database for Autism Research (NDAR) is a secure research data repository promoting scientific data sharing and collaboration among autism spectrum disorder (ASD) investigators. The project was launched in 2006 as a joint effort between five institutes and centers at the National Institutes of Health (NIH): the National Institute of Mental Health (NIMH), the National Institute of Child Health and Human Development (NICHD), the National Institute of Neurological Disorders and Stroke (NINDS), the National Institute of Environmental Health Sciences (NIEHS), and the Center for Information Technology (CIT). The goal of NDAR is to provide a shared common platform for data collection, retrieval, and archiving to accelerate the advancement of research on autism spectrum disorders. The