Complex knee injuries are a complex problem. When more than one ligament in the knee is torn, this is called a multi-ligamentous or poly-ligamentous injury. Unlike a more routine knee injury, such as an ACL tear by itself, the other supporting ligaments are also torn. This injury causes the knee to be unstable in more than one direction, which we call multi-directional instability. Using the best techniques, supported by the most up-to-date research, these patients are able to get back to their sport or work with the best function possible. The treatment of these injuries requires a thorough understanding of the anatomy and the different techniques to reconstruct them. Seeking the care of an orthopedic surgeon who routinely addresses these