The current investigation explored understanding of idioms in context in 93 children with communication disorders and 39 age-matched peers. The clinical group was subdivided by (a) the presence of autistic features and (b) the presence of language impairment. Idiom definitions were gathered in isolation and in context. Related skills such as semantics and theory of mind were also measured. All children benefited significantly from context. However, 2 groups with language impairments (1 with and 1 without autistic features) did not benefit from context as much as the controls or a group of children with autistic features without additional language difficulties. Regression analyses found that age, memory for story context, and language abilities were significant predictors of idioms in context performance. These findings are discussed in relation to theories of idiom acquisition and contextual processing in autism.KEY WORDS: specific language impairment, autism, idioms, context