Clinically significant anxiety occurs frequently among individuals with autism spectrum disorders (ASDs) and is linked to increased psychosocial, familial, behavioral and academic impairment beyond the core autism symptoms when present. Although efforts are underway to establish empirically supported treatments for anxiety among individuals with ASDs, this remains an emerging research area. This literature review summarizes available information on the efficacy of pharmacological and psychosocial approaches for treating anxiety and repetitive behaviors in children, adolescents and adults with ASDs. Specifically, we evaluate evidence for the use of cognitive-behavioral therapy and selective serotonin-reuptake inhibitors. Evidence is growing in support of using cognitive-behavioral therapy to treat anxiety in youths with ASDs; however, mixed evidence exists for its application in treating repetitive behaviors, as well as the use of selective serotonin-reuptake inhibitors for anxiety in youths with ASDs. We conclude the article with a discussion of the strength of current information and next steps in research.