Adolescence is a critical period of substance use and substance use disorders (SUD). Social exchanges within the context of adolescent friendships are key to understanding peer influences on the development of SUD. In this study we tested whether dyadic conversations between friends at age 17 are predictive of lifetime SUD diagnosis assessed at age 27. In controlled lab sessions, we observed conversations of 497 17-year-old adolescents and a friend. We coded the general way adolescents talk about deviant actions (i.e., deviancy training), but also specific positive talk about drugs (i.e., drug use talk). At age 27, a diagnostic interview was completed to assess lifetime SUD. Independent sample t-tests (in a selection of substance naïve participants to rule out that potential links would be driven by previous substance use) and structural equation modeling (integrated models, controlling for relevant covariates) were used to test whether deviancy training and/or drug use talk were predictive of lifetime SUD-diagnosis 10 years later. No significant links were found between deviancy training and SUD. Independent sample t-tests and integrated models showed significant associations between drug use talk about alcohol and alcohol use disorder and between drug use talk about cannabis use and cannabis use disorder. The link between talking about hard drugs and hard drug use disorder was marginally significant. Findings illustrate the risk of adolescent social learning in drug use talk with friends based on only 10 minutes of interaction, on the prediction of lifetime SUD assessed 10 years later and informs early interventions to curtail development of SUD. (PsycInfo Database Record (c) 2022 APA, all rights reserved).