To determine whether adolescent alcohol use and/or other adolescent health risk behaviour predisposes to alcohol dependence in young adulthood. Seven-wave cohort study over 6 years. A community sample of almost two thousand individuals followed from ages 14-15 to 20-21 years. Diagnostic and Statistical Manual volume IV (DSM-IV) alcohol dependence in participants aged 20-21 years and drinking three or more times a week. Approximately 90% of participants consumed alcohol by age 20 years, 4.7% fulfilling DSM-IV alcohol dependence criteria. Alcohol dependence in young adults was preceded by higher persisting teenage rates of frequent drinking [odds ratio (OR) 8.1, 95% confidence interval (CI) 4.2, 16], binge drinking (OR 6.7, 95% CI 3.6, 12), alcohol-related injuries (OR 4.5 95% CI 1.9, 11), intense drinking (OR 4.8, 95% CI 2.6, 8.7), high dose tobacco use (OR 5.5, 95% CI 2.3, 13) and antisocial behaviour (OR 5.9, 95% CI 3.3, 11). After adjustment for other teenage predictors frequent drinking (OR 3.1, 95% CI 1.2, 7.7) and antisocial behaviour (OR 2.4, 95% CI 1.2, 5.1) held persisting independent associations with later alcohol dependence. There were no prospective associations found with emotional disturbance in adolescence. Teenage drinking patterns and other health risk behaviours in adolescence predicted alcohol dependence in adulthood. Prevention and early intervention initiatives to reduce longer-term alcohol-related harm therefore need to address the factors, including alcohol supply, that influence teenage consumption and in particular high-risk drinking patterns.