This paper discusses the development of estimates of the lifetime costs of injuries for 1985. Total costs are estimated to be $158 billion for the 57 million persons injured in 1985. Updating these costs to 1988, the results are even more impressive-$182 billion. We describe the methodology for estimating costs and discuss theoretical issues and past research. We develop an injury cost model to estimate direct costs, morbidity costs, and mortality costs. Cost estimates are presented by type of cost, age, sex, cause of injury, and class of injury. Finally, we explore the implications of our results for public health policy.