This study focused on the openness of communication in teenagers' relationships with mother, father (or parental figure), and closest friend, and its correlation with teenagers' use of cigarettes, alcohol, marijuana, and other drugs. The predictive value for substance use of perceived pressure from friends, friends' substance use, and parents' substance use was also analyzed. The findings from questionnaires and interviews conducted with 37 students at an urban and a suburban/rural high school in New England are reported. The results suggest that the degree to which adolescents talk openly with their parents may influence the extent of their substance use. The presence of at least one "open" parental figure was associated with lower levels of all substance use. However, there was no evidence that openness with a close friend or perceived pressure from friends is related to substance use.