The field of autism spectrum disorders (ASDs) is expanding at an exponential rate. New topics for study are forming and journals are emerging rapidly to handle the ever-increasing volume of publications. This study was undertaken to provide an overview of past and current research trends. Representative studies were evaluated for type of content for each study, frequency of publications on given topics, journals that publish ASD research, and trends in publications over time. Autism was by far the most frequently studied of the ASD, followed by Rett and Asperger's Syndromes. The number of studies published on ASD continues to increase and the most frequently studied topics include genetics, perception and cognition, neurobiology, physiology and nosology. Some observations relative to the status of the field are presented and implications for the future are described. (Contains 3 tables.)