The young but burgeoning field of autism research continued its exponential rate of discovery in 2011—fueled in no small part by the joint commitment by government health agencies and private organizations to support this vital work. Our Top Ten Autism Research Achievements of the year include game-changing discoveries in how frequently autism recurs in families and the extent to which “environmental,” or non-genetic, influences increase the risk of autism in those who are genetically predisposed to this developmental disorder.Autism research also went global as never before in 2011, beginning with a study in South Korea that used community screening to discover a far higher prevalence of autism—1 in 38 schoolchildren—than standard surveys of medical records would have revealed.Meanwhile, the increased pace of genetic discoveries moved autism research into the realm of translational research—with basic science advancing to a level that makes rational drug design possible. Research also delivered immediate benefits with evidence that adequate folic acid around the time of conception may lower autism risk and the validation of a method for screening at one year that may enable earlier intervention to improve children’s outcomes. As never before, our list of the year’s Top Ten Autism Research Achievements only scratches the surface of a tremendously exciting year of discovery. We hope you’ll enjoy.Table of Contents(Order does not imply relative importance.)