We studied 78 inpatients with DSM-III major depression. Forty-one (53%) had a concurrent personality disorder (PD) according to a detailed structured interview for DSM-III personality disorders. The patients with depression plus PD differed from patients with depression alone on numerous measures. The PD patients had earlier onset; higher HRS scores; poorer social support; more life stressors; more frequent separation and divorce; more frequent nonserious suicide attempts, less frequent dexamethasone nonsuppression; poorer response to antidepressant medication; and higher risk for depression, alcoholism and antisocial personality among first-degree relatives. The PD subgroup shares many attributes with Winokur's subtype of depression spectrum disorder and Akiskal's character spectrum disorder. An attempt to identify a subgroup of personality disorders which might be an atypical affective disorder was inconclusive. However, patients in DSM-III cluster III were similar to the patients with no-PD on the dexamethasone suppression test, response to treatment, and familial risk for depression and antisocial personality.