Perpetual Children is a narrative history of debates over the definition and appropriate treatment of autism in France since 1950, noting the French divergence from psychological norms in the rest of the world. Examining the works of psychoanalysts, the activities of parents' associations, and the efforts of autistic self-advocates, the book argues that the consistent framing of autism as a form of childhood psychosis marginalized autists and emphasized the voices of parents and professionals. This framing also justified the continued use of psychoanalysis as an intervention due to the placement of autism within the family dynamic. Even as research in the United States pointed to biological and neurological conceptions of autism, the French continued to support a psychogenic origin for the disorder, impacting state policy and medical norms for decades. This position energized conflict between professionals and parents concerning expertise, leading to political and legal changes at the end of the twentieth century. By the twenty-first century, French autists entered the debate to transform its parameters and assert their own position as experts on autism, reconceiving the disorder outside of childhood to a limited degree. Perpetual Children reveals the international dimension of the story of autism and how the French context provides a different perspective on its history.