Brain injury is a term that denotes an acquired brain injury due to the action of an external mechanical force. Traffic accidents and falls are the most common causes of head and brain injuries. The annual incidence of TBI globally is estimated to be 27 to 69 million. TBI is the leading cause of disability on a global scale. Injuries can be focal and diffuse, open or penetrating and closed or non-penetrating. TBI is most often divided according to the degrees of clinical severity of the injury into severe, moderate and mild TBI. The clinical severity of TBI is assessed by the GCS scale. Neuroradiological classification relies on CT-based scales. In clinical practice, the Marshall scale and the Rotterdam scale are used. In pathophysiology we differentiate between primary and secondary brain injury. Primary injury occurs at the moment of external force. Secondary injury represents a series of molecular mechanisms that arise as a result of brain trauma, and develop hours and days after the action of the primary cause. The main treatment efforts are focused on the secondary brain injury. Treatment procedures include all measures of prevention and treatment of elevated ICP, maintenance of optimal CPK, optimal oxygenation and blood pressure, regulation of temperature, glucose, prevention of post-traumatic seizures and progression of secondary brain damage. Hypotension and hypoxia are the main factors that contribute to the progression of secondary brain injury, which are treated initially. Neuromonitoring (devices for dynamic monitoring of physiological parameters of the CNS) used in intensive treatment can help to assess pathophysiological processes and adjust therapy.