Major neurovascular injury is the least common, but most distressing, complication of total hip arthroplasty (THA). The keys to minimizing the incidence of these complications are recognizing patients at risk and knowledge of the relevant anatomy. Partial sciatic palsy is the most common nerve injury. At least partial recovery can be expected in 70% to 80% of cases, with the remainder frequently displaying dissatisfaction with their surgery. Vascular injury is most frequently associated with the use of screws for fixation of structural grafts, acetabulur components, and protrusio rings or cages. An understanding of the acetabular quadrant system is crucial in minimizing these potentially catastrophic complications.