The cost-effectiveness of maintenance simulators is compared to that of actual equipment trainers for training military maintenance technicians. Maintenance simulators are as effective as actual equipment trainers when measured by student achievement at school; there is no difference in the job performance of students trained either way, according to supervisors' ratings (based on one study). The acquisition cost of maintenance simulators is less than that of actual equipment trainers; they cost less than 60 percent as much if development costs are included and less than 20 percent as much if only unit fabricating costs are considered. Acquisition and use of a maintenance simulator over a 15-year period would cost 38 percent as much as an actual equipment trainer (according to one life-cycle cost comparison). Since maintenance simulators and actual equipment trainers are equally effective and since maintenance simulators cost less, it is concluded that maintenance simulators are more cost-effective than actual equipment trainers. This finding is qualified because it comes from a limited number of comparisons, because effectiveness is based primarily on school achievement rather than on-the-job performance and because it is based primarily on acquisition rather than on life-cycle costs.