• A family study of agoraphobia (n = 20), panic disorder (n = 20), and nonanxious controls (n = 20) showed the morbidity risk for all anxiety disorders to be 32% among firstdegree relatives of agoraphobics, 33% among relatives of patients with panic disorder and 15% among relatives of controls. Relatives of agoraphobics were also shown to be at higher risk for alcohol disorders. Female relatives were found to be at greater risk for anxiety disorders, reflecting their increased susceptibility to these illnesses, and male relatives were at greater risk for alcohol disorders. The increased risk for anxiety disorders in the relatives of agoraphobics was not specific for agoraphobia but included panic disorder and other phobias as well. The findings indicate that agoraphobia is a familial disorder and that family data may help to determine whether agoraphobia is separate from other anxiety and phobic disorders.