Posterior cruciate ligament (PCL) injuries are still often overlooked and treatment of a ruptured PCL is inherently different in comparison to anterior cruciate ligaments (ACL). Conservative treatment is the first-line therapy for acute isolated PCL injuries leading to good clinical and biomechanical results. Injuries to the PCL combined with rupture of other stabilizing ligaments, such as the collateral ligaments or the posterolateral corner of the knee joint are treated surgically. The same is true for high grade chronic PCL insufficiency. Meticulous classification of PCL injuries taking all stabilizing factors of the knee joint as well as the time from injury into account are essential for successful treatment of PCL injuries.