Each year, the IACC releases a list of scientific advances that represent significant progress in the field. The 20 studies selected have provided new insight into characteristics of high-risk siblings of children with autism spectrum disorder (ASD), molecular changes underlying the biology of ASD, and risk factors for neurodevelopmental disorders. The advances also include studies that examined promising communication interventions, the effects of policy changes on ASD service delivery, health and employment outcomes for adults with ASD, and the latest data on ASD prevalence in the U.S. The 2016 Summary of Advances provides short, plain language summaries of the top research breakthroughs selected by the IACC from a pool of research articles nominated by the members. Articles are grouped according to the topics represented by the questions of the IACC Strategic Plan for ASD Research. Citations for the articles selected for the Summary of Advances, as well as a complete listing of those nominated, are included at the end of the document.