Fibular collateral ligament (FCL) injuries can lead to varus instability of the knee, causing a varus thrust gait and resulting in increased forces on the medial compartment of the knee. In the long term, this can result in meniscal injuries and medial compartment osteoarthritis. Varus instability is also reported to increase forces on the cruciate ligaments, which can lead to overload and failure of these reconstructions in cases of nonrecognized combined injuries. Historically, both repair and reconstruction have been used for grade III injuries to the FCL. However, repair has been reported to lead to a higher reoperation rate. The hereby presented reconstruction technique is used for FCL injuries that do not involve other structures of the posterolateral corner, but can be used in combination with other knee ligament reconstructions including the posterior cruciate ligament, anterior cruciate ligament, and medial collateral ligament. The purpose of this surgical technique article was to describe the biomechanically validated anatomic reconstruction of the FCL using a semitendinosus graft.