In their prospective, randomized, single-blind phase II clinical trial of patients with Parkinson Disease (PD), Dr. Hacker et al. had previously shown that deep brain stimulation (DBS) of the subthalamic nucleus (STN) can slow progression of tremor and reduce the dopaminergic treatment requirement in patients with early PD. In their 5-year follow-up study published in Neurology, the investigators report the safety and tolerability of this neurosurgical intervention. Importantly, there were numerically similar adverse events with DBS as with best medical therapy (66 vs 68), with 5 events being procedural complications (2 neurocognitive complications and 1 case each of postprocedural hematoma, surgical scar, and pneumocephalus). Compared with medical therapy, STN DBS reduced the long-term severity of dyskinesias and dopamine treatment requirement and was associated with clinically significant improvements in several standardized Parkinson Disease metrics. Although these results are encouraging, independent comments by Drs. Fasano and Bhowmick and by Dr. Sidiropoulos would caution the interpretation that STN DBS may reduce the risk of disease progression. The authors acknowledge the limitations of this phase II study and are optimistic that the ongoing phase III randomized clinical trial will put this question to rest.