Knee-related complaints are among the most commonly encountered conditions by orthopaedic surgeons. Knee pathology varies widely and includes arthritis, deformities, fractures, infections, neuromuscular disorders, oncologic diseases, and soft-tissue injury. While nonoperative treatment modalities (activity modification, medications, injections, and physical therapy) are typically used as primary interventions, surgical treatment may ultimately become necessary. The purpose of this review is to discuss the most common open approaches to the knee, with an emphasis on surgically relevant anatomy for each approach. Understanding of the anatomy of the knee joint and associated neurovascular structures is necessary in order to avoid intraoperative complications and optimize postoperative recovery.