Failure to correctly tension grafts may overconstrain or underconstrain the knee, potentially predisposing the patient to deteriorating clinical and/or radiographic results over time. Knee ligament reconstruction requires a fundamental understanding of native anatomy, ligament biomechanics, and principles of graft tensioning. A successful strategy for graft tensioning takes into account the specific biomechanics of the ligament or ligaments in question, the mechanical properties of the graft selected, the chosen fixation method, the selected tensioning method (ie, manual or mechanical), and the overall goal of the reconstruction (ie, isometry versus anisometry).