Data from the Epidemiologic Catchment Area study showed that a lifetime Diagnostic Interview Schedule/DSM-III diagnosis of panic disorder was associated with pervasive social and health consequences similar to or greater than those associated with major depression. These consequences included subjective feelings of poor physical and emotional health, alcohol and other drug abuse, increased likelihood of suicide attempts, impaired social and marital functioning, financial dependency, and increased use of psychoactive medications, health services, and the hospital emergency department for emotional problems. Comorbidity of panic disorder with major depression, agoraphobia, and alcohol or other drug abuse did not explain these findings. The social and health consequences of panic disorder (quality of life) should be considered, as risks and benefits of currently available acute and maintenance treatments are evaluated. Clinical trials of panic disorder, whether of drugs or behavioral treatment, should include quality of life assessments as outcome measures. Long-term prospective studies based on clinical samples of patients with panic disorder are indicated to relate the illness more precisely to social morbidity.