The use of the knee, as well as the use of the elbow, in Muaythai is a unique art by which anyone seeing the fight will immediately identify it as Thai boxing. Practicing the use of the knees in a fight involves some difficulties and though it is not hard to learn is hard to execute properly and effectively. With successful practice it can be a great weapon for close-range engagement. The animation presents the art of knee work in a variety of forms, which can be divided in two categories, namely, hand-free/arm-free knee use and knee use with the aid of the hand or arm. Knee use has to be practiced in pairs. Hence, the student should thoroughly learn the theory before practical application in order to prevent any possible injury or accident. Each item of knee work is precisely described step-by-step, with animated illustrations and useful tips to ensure clear understanding and visualization.