The authors retrospectively compared 1-year results of bilateral deep brain stimulation (DBS) of the subthalamic nucleus (STN; n = 16) and internal pallidum (GPi) (n = 11) in advanced PD and found about equal improvements in "off" period motor symptoms, dyskinesias, and fluctuations. STN stimulation reduced medication requirements by 65% and required significantly less electrical power. These advantages contrasted with a need for more intensive postoperative monitoring and a higher incidence of adverse events related to levodopa withdrawal.