Posterolateral corner injuries of the knee are usually associated with injuries to other structures of the knee. It is not unusual to miss this injury during the initial assessment. Undiagnosed and untreated posterolateral corner knee injury leads to significant morbidity including early osteo-arthritis of the knee. Failure to recognise and reconstruct posterolateral corner injuries is one of the important reasons for the failure of cruciate ligament reconstruction surgery. In this article we have reviewed the literature regarding anatomy, biomechanics, clinical features and treatment of the posterolateral corner injuries of the knee.