This classic discusses Arthur E. Ellison's (1926-2010) contributions to our understanding of anterolateral rotatory laxity of the knee. Ellison was a distinguished orthopaedic surgeon and one of the founding members of the American Orthopaedic Society for Sports Medicine (AOSSM). He served as the team physician for the United States ski team and Williamsburg football team. Ellison's publications focussed on the pathodynamics of knee stability, shedding light on the biomechanical functions of the iliotibial band. This led to the development of his lateral extra-articular procedure designed to control excessive tibial rotation in the anterior cruciate ligament (ACL) deficient knee. His work has made a significant contribution to our understanding of knee stability today, and many surgeons still use a modified version of Ellison's original technique to augment ACL reconstruction. This article summarises Ellison's original publications and the first description of his operative technique. The impact of his work is discussed in the context of modern practice. The aim of this study is to add these valuable insights to the current discussion regarding the optimal method for lateral extra-articular tenodesis. LEVEL OF EVIDENCE: V - Expert Opinion.