The hypothesis was tested that weak theory of mind (ToM) and/or emotionrecognition (ER) abilities are specific to subjects with autism. Differences in ToM and ERperformance were examined between autistic (n = 20), pervasive developmentaldisorder—not otherwise specified (PDD-NOS) (n = 20), psychiatric control(n = 20), and normal children (n = 20). The clinical groups were matchedperson-to-person on age and verbal IQ. We used tasks for the matching and the contextrecognition of emotional expressions, and a set of first- and second-order ToM tasks. Autisticand PDD-NOS children could not be significantly differentiated from each other, nor could theybe differentiated from the psychiatric controls with a diagnosis of ADHD (n = 9). Thepsychiatric controls with conduct disorder or dysthymia performed about as well as normalchildren. The variance in second-order ToM performance contributed most to differencesbetween diagnostic groups.