A review of the life-time occurrence of major depression, the temporal relationship of major depression to episodes of panic and agoraphobic disorders, and the severity of anxiety and depressive symptoms were determined in 60 patients with agoraphobia or panic disorder. Forty-one (68%) of the patients had a past or current episode of major depression, and 35 (85%) of these patients had endogenous-type major depression. Twenty patients (33%) had an episode of primary major depression, and an average of three years separated the end of primary major depression and the first panic attack. Secondary major depression occurred in 28 patients. Patients with a history of major depression had a more severe anxiety disorder. These data support the view that in a subgroup of patients, episodes of depression and panic anxiety disorder may be manifestations of a common underlying pathogenic process.