This study, with an eye toward the social psychology of diagnosis more generally, is an investigation of how clinicians diagnose children with autism spectrum disorder (ASD). Responding to Hacking’s call for a Goffmanian mode of analysis to complement and balance the emphasis on large-scale transformations and discourses, we examine the narrative way in which clinicians provide evidence to support a diagnostic position. Using recordings and transcripts of clinical visits across two eras, our findings about the interaction order of the clinic show distinct story types and components that contribute to diagnostic narratives for ASD. These include stories about concrete “instantiations,” stories that propose “tendencies,” and “typifications” or generalizations regarding a specific child. This work contributes to interaction order theory, methodology, and other domains of social psychological research.