This research project is an ethnographic study of the communication technologies and social practices that enable the formation and maintenance of community among adults with autism, a group that is widely dispersed across online and offline spaces. This study focuses on adults who self-identify as autistic people and explicitly claim membership in an "autistic community." Autistic people are still typically understood to be asocial and socially uncoordinated, making the very notion of a community of autistic people, and efforts to continue its development, a significant challenge to enduring beliefs about what autism is, how it works, and how people with autism operate in the social world. This study employed ethnographic research methods, including participation in online and offline groups and spaces that autistic adults use regularly and interviews, to learn about three key things: First, this research entailed exploring how autistic community and the social practices and communication technologies that facilitate its continued development, both online and offline, demonstrated the ways various forms of expertise on autism interacted with — and were contested by — the lived experience of autism and autisticness. Second, I sought to learn what a "community" of autistic adults looked like and how it might work online and offline. Here, it was important to examine the inclusionary and exclusionary practices of the autistic spaces in which I studied. Finally, this research investigates the ways that sociocultural identity and self-knowing intersect with the ways people resist, transform, and reify the various classifications they are assigned to and accept. This study highlights the ways that cultural discourses of autism, autisticness, and normalcy shape autistic people's interactions with one another and the broader social world.