Stereotypy is a relatively common behavioral disorder displayed by individuals with developmental disabilities, including autism. In this paper, we review selected studies on neurobiological interpretations of stereotypy and pharmacological interventions for stereotypy. Specifically, we review studies that evaluated the effects of serotonin uptake inhibitors (e.g., clomipramine) or opioid antagonists (e.g., naltrexone) on stereotypy displayed by humans. Throughout, suggestions are made for the incorporation of behavioral methods into this area of research.