Autism is a deeply contested condition. To some, it is a devastating invader, robbing families of their children and sufferers of their personhood. To others, it is a form of neurodiversity, a fundamental and often valued aspect of identity that is more similar to race or gender than to disease states. How do young people coming of age with an autism spectrum diagnosis make sense of this conflict in the context of their own developing identity? The book addresses this question through sustained ethnographic engagement, informed by both clinical psychology and anthropology, within communities where people on the autism spectrum come together to live, learn, work, love, and play. Using an approach known as clinical ethnography, the book tracks neuroscientific discourses as they are adopted, circulated, and transformed among those affected by Asperger’s syndrome and related autism spectrum conditions. Dominant ways of talking about autism, whether as invasive disease or as hardwired neurogenetic identity, share a fundamental presupposition: that the healthy self is sharply bounded and destroyed if it is altered. However, the subjective experiences of youth on the spectrum exceed the limitations of these medical models. Reaching beyond medicine for their narratives of difference and disorder, these youth draw instead on shared mythologies from popular culture and speculative fiction to conceptualize their experiences of discontinuous and permeable personhood. In doing so, they also pioneer more inclusive understandings of what makes us who we are.