Patient-related risk factors for ACL graft failure.- Avoiding the failed ACL: how to prevent ACL tears before they occur.- Diagnosis of failed ACL reconstruction.- Biomechanics and Etiology of ACL graft failure.- Technical causes of ACL graft failure.- Indications for revision ACL reconstruction.- Preoperative planning for revision ACL reconstruction.- Graft selection for revision ACL reconstruction.- How to handle a poorly placed femoral tunnel.- How to handle a poorly placed tibial tunnel.- Fixation in revision ACL reconstruction.- Single stage ACL revision reconstruction: indications and technique.- Two stage ACL revision: indications and technique.- Revising failed double-bundle ACL reconstruction.- The role of lateral extra-arcticular augmentation in revision ACL reconstruction.- Managing the infected ACL reconstruction.- Meniscus allograft transplantation in revision ACL reconstruction.- Cartilage surgery in revision ACL reconstruction.- Medial collateral ligament laxity in revision ACL reconstruction.- Posterolateral corner deficiency in revision ACL reconstruction.- Osteotomy for slope correction following failed ACL reconstruction.- Osteotomy for malalignment following failed ACL reconstruction.- Navigation for revision ACL reconstruction.- Approach to the multiply revised ACL knee.- Outcomes of revision ACL.