He went from flunking a year in high school to identifying a gap in scientific research on dopamine and smoking tobacco as an undergraduate sociology major. When the young Sean Barrett realized he couldn’t fill that gap through the lens of sociology, he switched to psychology and completed an honours project that served as the foundation for the rest of his career. Now Dr. Sean Barrett is a professor in the Department of Psychology and Neuroscience and head of the Dalhousie Substance Use and Addictions Lab. There he studies substances like tobacco and alcohol to better understand how various factors contribute to different addictive behaviours. Now that Canada has announced the approaching legalization of cannabis, becoming the second nation in the world to do so, Sean and other Canadian researchers like him will be able to access cannabis for studies more easily than ever before. Those studies will build the much-needed scientific knowledge on the substance and its uses. He talks to us about his life, research and how the legalization of cannabis impacts his lab.