As part of the Combating Autism Act of 2006, the members of the Interagency Autism Coordinating Committee are required to develop an annual "Summary of Advances" to describe each year's top scientific advances in autism spectrum disorder research. These advances represent significant progress in the early diagnosis of ASD, understanding the complex biology of the disorder, and identifying potential risk factors. They may also relate to work identifying effective treatments and services and studies of the national prevalence of ASD and necessary research infrastructure. The 2010 Summary of Advances provides short, plain language synopses of the top twenty research breakthroughs selected by the committee from a pool of 64 peer-reviewed articles nominated by the members. Articles are grouped according to 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 summary.