In recent decades a growing number of children have been diagnosed with autism spectrum disorder ASD a condition characterized by among other features social interaction deficits and language impairment. Yet the precise nature of the disorders impact on language development is not well understood in part because of the language variability among children across the autism spectrum. The contributors to this volume experts in fields ranging from communication disorders to developmental and clinical psychology to linguistics use innovative techniques to address two broad questions Is the variability of language development and use in children with ASD a function of the language such that some linguistic domains are more vulnerable to ASD than others Or is the variability a function of the individual such that some characteristics predispose those with ASD to have varying levels of difficulty with language development and use Contributors investigate these questions across linguistic levels from lexical semantics and singleclause syntax to computationally complex phonology and the syntaxpragmatics interface.