Abstract High-functioning autistic, specifically language-impaired, and normal children were administered word fluency tasks in which they were required to provide the names of animals and the names of vehicles. The exemplars provided by each subject for each category were assigned prototypicality ratings according to the norms of Uyeda and Mandler (1980). The autistic children provided less prototypic exemplars than did the language-impaired children or language-matched normals. The results support the notion that autistic children have a semantic processing impairment and that part of the basis for this impairment may lie at the level of organization within lexical categories.