Traumatic brain injury (TBI) remains a significant global health care problem and, in the United States, affects 2% of the population per year. Despite significant advances in our understanding of the pathophysiology of TBI, mortality remains high at 20%, with significant long-term neurologic deficits in 35% of survivors. A joint task force of the Brain Trauma Foundation and the American Association of Neurological Surgeons (AANS) has developed evidence-based guidelines in an attempt to address systematically the care of these patients. The results of such collaborative efforts have focused management on both the primary injury – the initial traumatic insult—and secondary injuries, the pathophysiologic events subsequent to the primary insult. Our goal is to help practicing anesthesiologists understand the pathophysiology of TBI to allow them to develop perioperative management strategies most consistent with available evidence and current guidelines. TBI is often a key element of multitrauma. Hence, anesthesiologists are often asked to provide care for these patients while surgeons tend to their associated injuries.