ObjectivesThis article attempts, from a psychopathological perspective, to clarify the clinical evolution of patients with ASD during adulthood and into old age, and to assess the risks and the chances. In addition, the article also attempts to address the experiences of these people confronted with their own aging, the death of loved ones, and their own mortality. This study of a cohort of 314 elderly patients can provide some data concerning these changes. MethodThe study of the cohort of 314 adult and aging patients makes it possible to specify several aspects of ASD in adulthood: level of severity, associated disorders and co-morbidities (psychiatric disorders, intellectual deficit, epilepsy, neurosensory disorders, genetics). At the clinical and psychopathological level, the behavioral disorders are described therein with reference to the dominant psychopathological modes of functioning: typical autistic modalities (notion of post-autistic recourse), symbiotic modalities, acute anxious exacerbations, depressive and manic functionings. ResultsPropose an elucidation of challenging behaviors (or problem behaviors) and make it possible to address them; demonstrate that their evolution during advancing age is rather favorable while insisting on the permanent vulnerability of certain subjects. Specify the main courses of action, insisting on spatial, temporal, and relational security; on the central place of care procedures (fundamental physiological needs, consideration of somatic pathologies, specific care with psychotropic drugs, psycho-corporal approaches); and on the attention paid to everyday life, a major therapeutic mediator, through maintaining a reasonable amount of activity. DiscussionThe approach proposed here confirms that the main problem facing adults diagnosed with ASD is that of associated disorders and psychiatric co-morbidities, more than that of the fundamental symptomatic particularities necessary for the diagnosis of ASD (the autistic tripod). This requires going beyond the notion of challenge behavior and adopting a functional perspective that ultimately reveals sometimes major psychic suffering and the adaptive attempts that these patients make to cope with it. ConclusionThe clinical work with this particular population confirms the need for structured institutional work, the only thing that can ensure the coherence of the approaches to working with this diverse patient population, one that is diverse, with generally favorable developments, but which still remains very vulnerable.