There was marked improvement in the outcome of neurosurgical patients in the past two decades. Thus, improvement can be related to many causes, including early resuscitation; recognition of harmful factors and prevention of these factors; and marked advancement of instruments and equipment of surgery and anesthesia. One of the important causes behind this improvement in the outcome of these patients is the introduction of the concept of neurosurgical ICU in practice. This ICU receives two types of patients; those with head or spinal cord trauma, and those admitted for postoperative care. The principles behind the practice of neurosurgical critical care have much in common with the rest of intensive care medicine. By comprehensive monitoring of important physiological variables and titrating specific therapy to those variables, we hope to give the patient’s injured tissue the best chance of repairing itself.