This systematic review investigated the effect of proprioceptive and balance exercise on outcomes following injury and surgical reconstruction of the anterior cruciate ligament (ACL). Five studies of high quality that offered empirical evidence by comparing one rehabilitation program to another were included in this review. There is some evidence that proprioceptive and balance exercise improves outcomes in individuals with ACL-deficient knees. Improvements in joint position sense, muscle strength, perceived knee joint function, and hop testing were reported following proprioceptive and balance exercise. Only one included study investigated proprioceptive exercise following ACL reconstruction. Benefits were noted in the proprioceptive group for measures of strength and proprioception; however, no benefits were noted for any measures of activity. No detrimental effects--such as increased passive joint laxity or decrease in strength--were noted when compared with standard rehabilitation programs for both ACL-deficient and ACL-reconstructed individuals. Further research is required to determine if proprioceptive and balance exercise improves long-term outcomes such as return to sport.