A subcategory of patients with borderline personality disorder (BPD) who also meet criteria for attention deficit disorder (ADD) has recently been described. The present case involves a young man with BPD and ADD who failed to respond to methylphenidate but experienced a marked reversal of anxiety, explosiveness, restlessness, and affective lability when treated with imipramine. Tricylics may prove to be helpful in borderlines who also meet criteria for ADD.