Three patients with PD developed manic behavior after bilateral implantation of electrodes for deep-brain stimulation (DBS). Common to all three patients were manic symptoms unremitting after levodopa reduction or stimulation "off," lower electrodes positioning caudal to the subthalamic nucleus area, postoperative DBS with the lower contacts (0) of the quadripolar electrodes, and resolution of the manic episodes coinciding with stimulation through higher contacts.