Neurosurgical treatment of pain is based on 3 concepts: 1) lesional techniques interrupt the transmission of nociceptive neural input by lesionning the nociceptive pathways (cordotomy, radicotomy...), they are indicated to treat morphine-resistant cancer pain; 2) neuromodulation techniques try to decrease pain by reinforcing inhibitory mechanisms, using chronic electrical stimulation of the nervous system (peripheral nerve stimulation, spinal cord stimulation, motor cortex stimulation...) to treat chronic neuropathic pain; 3) intrathecal infusion of analgesics (morphine, ziconotide), using implantable pumps, allows to increase their efficacy and to reduce their side effects. These techniques can improve, sometimes dramatically, patients with severe and chronic pain, refractory to all other treatments.