This policy brief provides an introduction to benefit-cost analysis and how it can assist policymakers and corrections officials in determining whether investing in supermax security facilities constitutes an appropriate and effective allocation of resources. The brief provides examples of practical applications of benefit-cost analysis, introduces the logic of this analytic tool, describes the specific steps involved in conducting a benefit-cost analysis, and then shows how these steps apply to supermax prisons. The brief emphasizes the critical role that informed judgments and assumptions play, along with empirical research, in affecting the results of benefit-cost analyses.