We examined the association between affective disorders and eating disorders in 22 eating disorder inpatients who were interviewed using the Schedule for Affective Disorders and Schizophrenia-Lifetime Version. The first series of 11 were interviewed as part of an interrater reliability study; the second series, done as follow-up to the first, consisted of 11 consecutive admissions. Overall, there were 15 bulimics and seven anorexics. Nineteen patients had a major affective disorder, and 13 (59%) had bipolar II affective disorder. Bipolar II affective disorder appears to be a common finding in hospitalized patients with severe persistent eating disorders.