This study is accordance with CAN research priorities in its focus on improving methodological approaches in clinical trials (Hollander, et al., 2004). This study is also consistent with recent NIMH recommendations for clinical research. The recommendations identify the integration of behavioral research methods with traditional methods of clinical research (i.e. group designs) as important aims for ASD treatment research (CPEA/STAART working group, 2004). As such, this study fills significant gaps in two research areas: treatments for repetitive behaviors and research methodology in treatment trials for individuals with ASD.