OBJECTIVES: In May 2013, the American Psychiatric Association released the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) which is a classification and diagnostic system for psychiatric and certain neurologic conditions.  DSM-5 brings significant changes to many of the diagnostic categories as compared to the previous edition of the manual.  The objective of this review was to examine the changes in the Autism Spectrum Disorder (ASD) criteria and discuss the impact of these changes for industry. METHODS: A line-by-line review of the DSM-5 criteria for Autism Spectrum Disorder and the DSM-IV criteria for Pervasive Developmental Disorders was undertaken.  Significant changes were highlighted and discussed from the point of view of sponsors of clinical trials for psychopharmacologic agents being developed to treat these conditions. RESULTS: The changes to the diagnostic criteria for what were known in DSM-IV as pervasive developmental disorders (PDD) are sweeping.  ASD, now in a section of the DSM titled “Neurodevelopmental Disorders,” is a single entity in DSM-5 with several levels of severity that effectively replaces the five PDDs that were separately classified in DSM-IV.  Notable changes include the addition of severity levels to the ASD criteria, changes to the social interaction and social communication criteria, and the addition of hyper- or hyporeactivity to sensory input or unusual interest in sensory aspects of the environment, as an illustrative example of restrictive, repetitive patterns of behavior, interests, or activities. CONCLUSIONS: The numerous and significant changes in DSM-5 pose both challenges and opportunities to industry.  We need to take a careful look at DSM-5 to understand what the changes mean for how we go about developing medical products to treat psychiatric disorders.  This means the need for investment in research, education, and new ways of approaching the development of endpoints and outcome assessments in clinical trials.