Autism spectrum disorders (ASD) are characterized by the presence of repetitive behavior and stereotyped patterns of interest and activities. It is common for clinicians to assume that repetitive behaviors are maintained by automatic reinforcement but, as with any challenging behavior, the function of stereotypy should not be assumed based on its topography. Previous research on the functional assessment of stereotypy has produced mixed results, and most previous studies on the functional assessment of stereotypy in children with ASD have included small sample sizes, so more research in this area is warranted. In the current study, indirect functional assessments consisting of the questions about behavioral function (QABF) were conducted across 53 children and adolescents with ASD. The QABF produced interpretable results in a high percentage of cases and 90% of the stereotypic behavior appeared to be maintained by automatic reinforcement. (Contains 1 table and 2 figures.)