Abstract Psychopharmacologic approaches to the treatment of patients with “borderline personality” have been aided by increasing refinement of the diagnostic term. The broadly conceived category of borderline personality organization includes numerous clinical syndromes with specific patterns of symptoms and response to medications. This paper reviews these syndromes in relationship to four psychopathologic “borders” of borderline personality disorder: schizophrenia, affective disorders, organic mental disorders, and personality disorders. Current psychopharmacologic approaches to the treatment of these syndromes are reviewed, and medication choice is discussed with respect to target symptoms. Compliance with treatment, often a problem with borderline patients, is discussed with respect to medication use.