Obsessive-compulsive disorder (OCD) is one of the most disabling mental illnesses. Despite the availability of several pharmacological and psychological treatments, 10% of patients are still severely affected by the disorder and are considered to have intractable OCD. For some of these patients, deep brain electrical stimulation (DBS) may be an appropriate treatment option. However, the efficacy and safety of DBS is unclear, and it is not known where the treatment target is more effective. For this reason, Jens Kuhn et al. from Germany conducted a systematic review with the aim of reviewing previously published data and comparing the differences in target structures and their efficacy. The findings suggest that deep brain electrical stimulation for refractory OCD is a relatively safe and promising treatment option. However, the optimal target structure for treatment is not yet clear. The study was published in a recent issue of BMC Psychiatry. The researchers used the terms “deep brain electrical stimulation” and “obsessive-compulsive disorder” to search PubMed for all literature published through June 2013. Of the total 25 studies retrieved, five different structures were reported as targets of deep brain electrical stimulation for OCD: the anterior limb of the internal capsule (14 patients in 5 studies), the ventral nucleus (37 patients in 8 studies), the ventral nucleus/ventral striatum (29 patients in 4 studies), the thalamic nucleus (23 patients in 5 studies), and the inferior peduncle of the thalamus (6 patients in 2 studies). Despite differences in anatomy, response rates after deep brain stimulation for the first 4 target structures were similar, with a higher response rate for deep brain stimulation in the subthalamic peduncle. However, caution is needed in interpreting these results because of the small sample size of cases. The incidence of surgical treatment, as well as device-related adverse events, was relatively low, as were stimulation- or treatment-related adverse reactions. Most of the stimulation-related adverse reactions were very transient and decreased after changing the stimulation parameters. The study concluded that deep brain electrical stimulation for refractory OCD appears to be a relatively safe and very promising treatment. However, based on these current findings, the optimal target structure for treatment cannot be clarified. More research is needed to better understand the mechanisms of action of this treatment approach and the predictors of treatment effectiveness to better help develop a more individualized treatment strategy for these severely affected OCD patients.