Autism, or the broader category of autistic spectrum disorder (ASD), is a complex developmental disability characterized by qualitative impairments in social interaction and communication and restricted repetitive patterns of behavior. Specific aims of the investigation reported here were to (a) compare autistic child behaviors in clinic versus home settings, (b) compare father and mother behaviors in clinic versus home settings, and (c) characterize interactions of fathers with their autistic children and compare these with mother-child interactions. While results indicated that there were no statistically significant group differences between child behaviors in clinic versus home settings or in father versus mother behaviors, there was wide behavioral variability in each setting and differences when comparing individual cases. These findings are consistent with the clinical impression that autism is a syndrome with various symptom configurations and individual differences in behaviors.