Many children today participate in highly organized sports programs that involve regimented year-round repetitive training. This type of training has led to an increased incidence of overuse musculoskeletal injuries. Sports physicians have dealt with sports injuries in children for many years and, on the basis of their clinical experience, have developed guidelines to treat and to try and prevent these injuries. The purpose of this article is to provide a biomechanical perspective of sports injuries in young athletes and blend ideas from this perspective with more traditional clinical perspectives that dominate the literature relative to this topic. Basic tissue and gross movement mechanics principles are used to identify growth, morphological, and movement factors that may predispose a child to an overuse injury. Several biomechanical analyses of simple movement tasks are presented to quantify the forces developed in various tissues and to illustrate the effects that growth can have on these forces. Guidelines are given for developing injury prediction models that may be used in the future to establish safe and effective training guidelines for children.