This study centers on repair sequences in institutional group therapy sessions between 11- to 13-year-old Finnish-speaking autistic boys and their therapists. The discussion covers inquiry of the prosodic and non-verbal features of trouble-source turns that launch other-initiated repairs. It is shown that ASD persons’ tilt to shun direct eye contact as well as the presence of some irregular prosodic features in their speech influence interaction fluidness and are linked to the emergence of misunderstanding. Yet they rarely seem the major cause of this. The two most general causes of understanding problems are excessively literal speech interpretation and topical discontinuities. The study also provides new proof about autistic persons’ pragmatic and interactional abilities. Indeed, the data involve passages in which the informants appear to be able to make some inferences about others’ mental states, which is noteworthy as it is known that the capacity in question is challenged in autism.