Medial patellar instability can be a disabling complication of an extensive lateral retinaculum release. It is often overlooked, and for the diagnosis, it is necessary to have a high index of suspicion. Typically, the patient feels a new pain and new instability after the lateral retinaculum release that are distinct from, and much worse than, those before surgery. All of our patients had significant relief from their pain with "reverse" McConnell taping. If there is a significant improvement in symptoms after this taping and stress radiographs or stress axial computed tomography scans show an objective pathologic medial patellar displacement, reconstruction of the lateral retinaculum should be considered. This article details our technique for reconstruction of the deep transverse layer of the lateral retinaculum using an anterior strip of the iliotibial band. This strip is detached from its insertion onto the Gerdy tubercle and then reflected proximally beyond the level of the lateral femoral epicondyle. Finally, it is attached either by direct suture to the remaining prepatellar and peripatellar retinaculum if there is adequate tissue present or by a suture anchor.