Medial-sided knee injuries are very common, the medial collateral ligament being the most commonly injured ligament of the knee. Injuries to the medial side of the knee can occur in isolation or concomitant with other knee ligament injuries. Isolated grade I and II injuries have been typically treated nonoperatively with excellent results. Isolated grade III injuries, however, are less common and more controversial. Although some recent literature has shown acceptable results with nonoperative treatment of isolated grade III injuries, most authors recommend surgical treatment. A variety of operative techniques have been described, including repair, augmentation, and reconstruction, all with favorable outcomes. Choice of treatment method should be based on injury pattern with the goal of regaining valgus and anteromedial rotatory stability of the knee.