Vagus nerve stimulation (VNS) therapy is the first US Food and Drug Administration-approved somatic clinical intervention for treatment-resistant depression (TRD). Long-term open data suggest a sustainable antidepressant response over time. Here we review the clinical data that exist so far and their limitations. We also discuss guidelines that may inform the clinical utilization of this procedure. Further clinical studies, in addition to prospective cost utilization and health economic investigations, are needed to better understand VNS therapy and the impact it holds on TRD care.