Book excerpt: Abstract ADOLESCENT SUBSTANCE USE: PERCEPTIONS OF PARENTS AND TEENAGERS. Drug use among Minnesota youth is a leading health risk behavior. This study examined rural adolescents' and parents'/guardians' perceptions of teens' substance use. An electronic survey was administered to high school students (n = 62; adjusted response rate = 84.9%) and sent by email to 79 parents/guardians (n = 22; adjusted response rate = 27.8%). Analyses included descriptive statistics, independent and paired sample t-tests, and chi-square. 56.5% of teens reported using alcohol in the past 12 months whereas 12.9% reported using marijuana. During the past 30 days teens reported using alcohol 1.1 days and using marijuana 1.2 days. When teenage participants did drink, they reported having 3.4 drinks on average. Teens estimated that 22.9% of close friends and 45.3% of peers used alcohol and 10.7% of close friends and 23.6% of peers used marijuana during the past 30 day. A significant difference between teenagers' and parents' perceptions of social norms related to substance use was identified. Differences in parental perceptions of alcohol use and reported teen alcohol use were found. Parents' perceptions were confirmed true when it comes to teenage marijuana use as no significant difference was found. Significant differences were found between student's perceptions of social norms and the substance use behaviors of teenagers. A significant difference was found between parents' perceptions of social norms related to substance use of their own child and the reported substance use behaviors of teenagers. Finally, a significant difference was found between teenagers' perceptions of social norms related to substance use among their close friends and their perceptions of social norms related to substance use among peers.