Substance use and levels of cohesion and adaptability were assessed in three consecutive high school freshman classes in a small midwestern city. As predicted, adolescents who perceived their families to be extreme on cohesion and adaptability (measured by FACES II) were more likely than adolescents from balanced and midrange families to use marijuana, alcohol, tobacco, depressants, and psychedelics. Inconsistent results were found for cocaine use. Adolescents from extreme families were especially vulnerable to substance use when a family member was perceived as having a drinking problem.