Teenage Substance Abuse part 2

John Knight, MD, is director of the Center for Adolescent Substance Abuse Research at Boston Children's Hospital. He has served as a consultant to the National Institute on Drug Abuse, The National Institute on Alcohol Abuse and Alcoholism, and the President's Office of National Drug Control Policy. In this interview, he talks about underage drinking, how to recognize a substance abuse problem and how parents can help their children learn to drink responsibly.