Deep brain stimulation (DBS) is a safe and effective treatment for medically refractory movement disorders such as Parkinson's disease, essential tremor and dystonia. The success of DBS in treating movement disorders with over 100,000 patient implants has revived interest in the use of DBS for the neurosurgical management of refractory conditions including epilepsy, psychiatric disorders (obsessive compulsive disorder, major depressive disorder, addictions, and eating disorders), neuropathic chronic pain, headaches, cognitive disorders, and traumatic brain injury. This manuscript provides a review of the current application of DBS surgery in movement disorders, psychiatric and other conditions.
  Additionally, an overview of the recent advances in our understanding of the neural circuitry underpinning the pathophysiology of these disorders is provided. The use of imaging and the latest surgical techniques to target these structures will be highlighted. Furthermore, new technology such as the introduction of the “closed loop system”, smart DBS devices, responsive brain stimulation and emerging neuromodulation approaches will be discussed.