The social skills and problem behaviours of children with high-functioning autism and Asperger's Disorder were compared using parent and teacher reports on the Social Skills Rating System. The participants were 20 children with high-functioning autism, 19 children with Asperger's Disorder, and 17 typically developing children, matched on chronological and overall mental age. The children with autism and Asperger's Disorder were not differentiated on any social skill or problem behaviour based either on teacher or parent report. However, both clinical groups demonstrated significant social skill deficits and problem behaviours relative to the typically developing children, and the original standardization sample. The findings were compatible with the view that autism and Asperger's Disorder belong on a single spectrum of disorder.