The Department of Defense (DoD) provides work for 3.7 million people—about 1.4 million Active Duty military, 800,000 in the National Guard and Reserves, about 750,000 government civilian employees, and another 750,000 contractor personnel. Some jobs require government employees (military or civilian). Some can only be done by individuals in uniform. Within these constraints, it is DoD policy to use the least expensive, suitable kinds of workers to fill particular jobs. Failure to follow this policy wastes money. This paper discusses the kinds of workforce mix changes that could be beneficial and focuses on specific cases in which the substitution of government civilians for military personnel would reduce costs. Areas addressed are medical personnel, education and training, the cyber workforce, and remotely piloted aircraft. The paper concludes with a discussion of the impediments to making appropriate civilianization decisions.