This study investigated the frequency and latency of naturally occurring social interaction with typically developing children and those with autism in inclusive kindergarten settings. The children with autism were also subdivided into two groups according to intellectual functioning in order to analyze frequency and latency of social interaction in relation to degree of disability. The results showed a significant difference in frequency of social interaction between the typical children and those with autism. There was no difference between the groups on latency to initiate interaction. However, shorter latency was associated with higher frequency in the typical group but not in the group of children with autism. Significant differences in IQ and adaptive functioning were found between the children with autism who showed interaction and those who did not. The results for the typical children may be used as benchmark values for the assessment of treatment outcome for children with autism. (Contains 2 tables and 1 figure.)