Sport has many physical and mental health benefits. But it is also the leading cause of injury in Canadian youth. Soccer is one of the most popular sports for girls, but 1 in 20 will suffer a serious injury every year. These injuries reduce quality of life, lower physical activity levels, and can have long-term impacts. For example, half of girls who have a knee injury will develop osteoarthritis, a painful, disabling joint disease with no cure. Convincing research shows that injury prevention programs can prevent two-thirds of injuries. Yet, in the real-world regular use of these programs by teams is low. This is partly due to a lack of sustainability planning and input from relevant stakeholders. This project will first address these issues in design and then will test an injury prevention program. We will involve soccer players, coaches, physiotherapists, and administration in all research. First, we will combine and consider research findings and learnings from world experts. Second, we will understand stakeholder needs and settings. Third, we will co-design a plan to implement and sustain the program in the long-term. Last, we will test if the program is feasible and acceptable for sustained use in community girls soccer.