No matter which impact evaluation design is employed, a cost-benefit analysis should be performed on its results to determine whether the program is operating efficiently--in other words, whether the benefits of the program outweigh the costs. In a time when budget constraints are widespread, cost evaluations can ensure efficient allocation and expenditure of funds.

Cost-benefit analyses estimate the benefit returned for each dollar a program spends. Typically, cost studies calculate total program costs, average the cost per client, and finally divide the total cost by the number of clients served. Linking this analysis to an impact evaluation leads to the estimate cost of each successful client. ^[1]   For instance, a cost evaluation can indicate whether a long-term employment program for returning state prisoners diverted future costs out of the criminal justice system. Evaluators can compare the cost of future incarcerations (or, more broadly, other law enforcement functions related to arrest and prosecution) to that of job training to determine whether the program yielded monetary benefits. A cost evaluation might also indicate whether the use of resources for job placement could have been more efficiently or effectively used for educational training, or perhaps substance abuse treatment.