We report the successful treatment of an episode of major depression with psychotic features with electroconvulsive therapy (ECT) in a 78-year-old woman with advanced Parkinson disease who had a left subthalamic nucleus deep-brain stimulator (DBS) in place. Electroconvulsive therapy effectively and safely treated the patient's depression without harming the patient or damaging the DBS hardware. We offer additional evidence about the safety and efficacy of electroconvulsive therapy in patients with DBS.