Thirty cadaveric knees were dissected to obtain a detailed understanding of the anatomic structures of the posterolateral aspect of the knee, and a dependable surgical approach to evaluate injuries to these structures was developed and used on 71 consecutive patients who were operated on for posterolateral knee injuries. Three fascial incisions and one lateral midcapsular incision were used to provide surgical access. The following individual anatomic structures were identified: the layers of the iliotibial tract, long and short heads of the biceps femoris muscle, fibular collateral ligament, midthird lateral capsular ligament, fabello-fibular ligament, posterior arcuate ligament, popliteus muscle complex, lateral coronary ligament, and posterior capsule. This study increased our understanding of the individual anatomic structures and the relationships between these components. The surgical approach provided for the evaluation of these anatomic structures should aid the surgeon in properly assessing the injuries before surgical repair. This information should also stimulate more anatomic, biomechanical, and clinical studies of the posterolateral aspect of the knee.