Autism spectrum disorders (ASDs) are among the most common childhood neurodevelopmental syndromes. A fundamental goal in the field is the discovery of methods that mitigate core autism symptoms, since lower levels of such symptoms are associated with better prognosis. The core symptoms tend to be stable and resistant to intervention. While social skills treatments are common for school-aged youth with ASD, the current evidence base is weak, with limited external validity and durability of effects. Cognitive behavioral therapy (CBT) offers a novel approach for addressing core autism symptoms in higher functioning school-age youngsters. In prior work by this research team, CBT has been successfully adapted to treat emotional problems in school-aged children with ASD. Initial results suggest that CBT may also be promising for reducing core autism symptoms. Fifty children with high-functioning ASD (7-11 years old) will be randomly assigned to 32 sessions of CBT or an attention placebo condition (social skills training, the standard of care in the community). An independent evaluator will administer a standardized assessment battery, including performance-based assessments (e.g., the ADOS) and school-based behavioral observations of children's core autism symptoms at pretreatment, post treatment, and 3-month follow-up. The treatment is based on a contemporary model of memory retrieval competition, employing strategies for enhancing the retention and enactment of adaptive conceptual and behavioral responses in daily social contexts (e.g., school, home), emphasizing the use of deep semantic processing to enhance memory retrieval. Quality assurance will be established via reliability checks and treatment fidelity monitoring. It is anticipated that children who receive this experimental CBT therapy will exhibit more improvement in core autism symptoms in school and home settings when compared to children who receive the social skills training intervention. This study would result in a novel, empirically based intervention for the treatment of core autism symptoms. Given the increasing prevalence of autism and the lack of effective treatment models in this age-group, positive findings from this study could have broad public health significance.