This chapter describes the psychopathology of the eating disorders and a cognitive-behavioral account of the mechanisms that maintain them. In DSM-IV a new provisional eating disorder diagnosis was termed as binge eating disorder. Consistent with the current way of classifying eating disorders, the research on their treatment has focused on the particular disorders in isolation. The transdiagnostic form of cognitive-behavioral therapy (CBT) is designed for the full range of clinical eating disorders seen in adults. Enhanced CBT is an outpatient-based treatment designed to be delivered on an individual basis. The initial assessment interview has two interrelated goals. The first is to put the patient at ease and begin to forge a positive therapeutic relationship. The other goal is to establish the diagnosis. Knowledge of the active ingredients of treatment would provide the basis for further enhancing these and omitting redundant ones.