Borderline personality disorders psychiatrists and psychotherapists at the Personality Disorders Institute: mental health professionalsThe Personality Disorders Institute (PDI) under the leadership of Otto F. Kernberg, M.D., director, and John F. Clarkin, Ph.D., co-director, is an internationally recognized group of mental health professionals examining the range of personality pathology, including that of borderline personality disorder, and developing empirically supported treatment for these patients. Individuals suffering from personality disorder are characterized by disturbances in self-definition and functioning, and disturbances in their interpersonal relations. Personality disorders are often accompanied by depression, anxiety, self-destructive and suicidal behavior, and serious disturbances in intimate relations, social relations, and work productivity.