Successful inclusion is facilitated when children with autism fit in and interact in meaningful ways with their typical peers. However, deficits in conversational language likely limit the social attractiveness of children with autism to their classmates. This study evaluated an incidental teaching approach to promoting use of age-appropriate social phrases by three preschool-aged boys with autism. A multiple baseline design demonstrated that introduction of incidental teaching yielded immediate use of the targeted social phrases ("All right" and "You know what?") during instructional sessions, and children transferred use of the new social phrases to unprompted conditions. Initial instruction required somewhat artificial stimulus-response relationships to compensate for the lack of responsiveness to social consequences that characterizes autism. However, as in other studies in which conversational language was successfully taught to children with autism, systematic fading procedures facilitated transfer of stimulus control from the contrived cues needed to teach a child with autism to say age-appropriate social phrases to conditions that call for comments and queries in everyday situations. (Contains 2 figures.)