This study examined the relationship between severe traumatic events and alcohol use disorders in American Indian adolescents and young adults. Interviews of 432 adolescents and young adults who were enrolled tribal members living on or near two closely related American Indian reservations were used. Results indicated that severe trauma increased the odds of alcohol use disorders (p <.001), with the number of traumas having a dose-dependent effect. The authors conclude that trauma is associated with alcohol use disorders in this population. This study's findings yield important insights into the risks in American Indian adolescents and young adults that may result from early trauma, as well as implications for the timing and possible settings for intervention.