Available information indicates that as many as 75 of children with autism spectrum disorder ASD have language delay ranging from mild to severe. Many interventions have been developed to address language delay including intensive treatment using applied behavior analysis ABA. Although often effective for severe language delay e.g., children with no language,intensive ABA intervention may not be needed for children with moderate language delay. Untreated moderate language delay predictably interferes with the childs ability to advance in the social and academic domains. Direct Instruction Language for Learning DI-LL is a highly structured intervention with empirical support in children with language delay uncomplicated by autism spectrum disorder. However, DI-LL has not yet been carefully studied in children with ASD. As in ABA, the DI-LL curriculum incorporates immediate reinforcement for correct responses, immediate and systematic error correction procedures, shaping, prompting, and fading. To date, there is only one small study of DI-LL in children with ASD and language delay. The purpose of this study is to test the efficacy of DI-LL in a six-month randomized trial in 100 children with ASD and moderate language delay. Eligible subjects will be randomly assigned to DI-LL or Treatment As Usual TAU for 6 months.