Deep brain stimulation (DBS) is considered a highly effective therapy for all cardinal symptoms of Parkinson's disease (PD) and levodopa-induced motor complications. DBS is based on the empirical observation that high-frequency electrical stimulation of specific brain targets can mimic the effect of a lesion without the need for destroying brain tissue. DBS is accomplished by permanently implanting an electrode into the target area and connecting it to an internal pulse generator. The stimulator settings can be adjusted telemetrically with respect to electrode configuration, current amplitude, pulse width, and pulse frequency. DBS essentially mimics the clinical effects of lesioning in all three target structures currently used for the treatment of PD―namely, ventrolateral thalamus, internal pallidum, and subthalamic nucleus (STN), when high-frequency (> 100 Hz) stimulation (HFS) is applied. DBS is considered an alternative for ablative stereotactic surgery in movement disorders with several advantages, such as: (1) DBS does not require a destructive lesion to be made in the brain, (2) DBS can be performed bilaterally with relative safety, (3) stimulation parameters can be adjusted postoperatively to improve efficacy, to reduce adverse effects, and to adapt DBS to the course of disease, and (4) DBS is reversible and does not preclude the use of possible future therapies in PD requiring integrity of the basal ganglia circuitry.