Beef cattle production is done within a system that includes grazing on large amounts of land per cow; being fed high-calorie diets for a few months in large populations immediately prior to slaughter; long gestation and growth periods so that animals are sold for food 2-3 years from the time they were conceived; and, in most situations, more than two changes of ownership from birth to being sold for food. Because of the long time lags and multiple changes in ownership between intervention decisions and health and economic outcomes, a systems approach is necessary to accurately evaluate numerous potential management interventions to optimize animal health and productivity.