Objective: This pilot study examined whether contract case managers are cost effective in reducing workers' compensation (WC) costs and preventing injuries. Methods: We placed contract medical case managers at four installations where they employed private industry best practices. A needs assessment was performed and site-specific targeted interventions were developed. Case managers improved WC program effectiveness by ensuring command support, and strengthening the case management process. They minimized lost work time and provided the WC team resources to review the oldest cases. Results: Case managers cost $1.25 million and they generated $4.4 million in savings for a 3.52 return on investment. Case managers removed 73 workers from long-term rolls by making use of vocational rehabilitation, finding modified duty jobs, offering workers medical retirement, and terminating benefits when workers refused to work after being offered a job. Conclusions: This study of medical case managers demonstrates they can reduce WC costs.