Background: Since bulimia nervosa's introduction to the psychiatric nomenclature in 1979, data concerning long-term outcome have been largely unavailable. Methods: Women with the diagnosis of bulimia nervosa between 1981 and 1987 who participated in 1 of 2 studies were located and invited to participate in follow-up assessments. Results: More than 80% of the women from these studies participated in follow-up assessments and the results represent findings for 173 women more than 10 years following presentation (mean±SD length of followup, 11.5±1.9 years), 11% of this sample met full criteria for bulimia nervosa, and 0.6% met full criteria for anorexia nervosa. An additional 18.5% met criteria for eating disorder not otherwise specified, and 69.9% of this sample were either in full or in partial remission. For predictive factors, only the duration of the disorder at presentation and history of substance use problems demonstrated prognostic significance. Baseline treatment condition was not associated with remission of disordered eating symptoms by the follow-up assessment. Conclusions: The findings suggest that the number of women who continue to meet full criteria for bulimia nervosa declines as the duration of follow-up increases; approximately 30%, however, continued to engage in recurrent binge eating or purging behaviors (incidence rate, 0.026 cases per person-years). A history of substance use problems and a longer duration of the disorder at presentation predicted worse outcome.