Injury to the anterior cruciate ligament (ACL) is common and affects young individuals, particularly girls, who are active in sports that involve jumping, pivoting, as well as change of direction. ACL injury is associated with potential long-term complications including reduction in activity levels and osteoarthritis. Multiple intrinsic and extrinsic risk factors have been identified, which include anatomic variations, neuromuscular deficits, biomechanical abnormalities, playing environment, and hormonal status. Multicomponent prevention programs have been shown to be effective in reducing the incidence of this injury in both girls and boys. Programs should include a combination of strengthening, stretching, aerobic conditioning, plyometrics, proprioceptive and balance training, as well as education and feedback regarding body mechanics and proper landing pattern. Preventive programs should be implemented at least 6wk prior to competition, followed by a maintenance program during the season.