The removal of space-occupying lesions in the sensori-motor cortex carries a considerable risk of postoperative palsy. Therefore subcortical lesions located in the sensori-motor strip are often considered to be inoperable. Treatment options are stereotactic biopsy and radiosurgery beside radiological control examinations without surgery or surgery with a higher risk of postoperative deficits. The following article focusses on a combined approach involving a stereotactically guided and electrophysiologically controlled surgery. The instruments used (stereotactical system and electric stimulator) are available in almost every neurosurgical department in the Western and Eastern world and had been the first navigation systems in the human brain.