Dr. Carl Hart is an Associate Professor in both the Departments of Psychiatry and Psychology at Columbia University and is also a Research Scientist in the Division of Substance Abuse at the New York State Psychiatric Institute. A major focus of Dr. Hart's research is to understand the complex interactions between neurobiological and environmental factors that mediate and modulate the actions of drugs of abuse, including drug-taking behaviour and cognitive performance. Dr. Hart's research has been supported by the National Institute on Drug Abuse for the past several years. In addition to his substantial research responsibilities, Dr. Hart teaches an undergraduate Drugs and Behaviour course and was recently awarded Columbia University's highest teaching award.