The worlds largest bureaucracy is too big and too complex not to have major management problems. The Department of Defense has an annual budget of more than $700 billion, which is transmitted to Congress with more than 100 separate volumes of supporting materials. It runs the largest acquisition systemin the world, spending hundreds of billions of dollars annually on everything from nuclear submarines and hypersonic research to truck tires and accounting services. It has a workforce of almost three million active and reserve service members and civilians, who do everything from flying aircraft to delivering babies. As I have argued elsewhere, the Department is more like an economy than a business. Secretary of Defense Mark Esper has prioritized management issues, personally leading a zero-based budget review to free up resources for modernization. Management reform requires more than generating savings, however, and there is a risk that the Departments recurring emphasis on cutting programs may squeeze out needed improvements to organizations, policies, and practices. No secretary of defense will ever be able to fix the Departments management problems, but a secretary who can make measurable improvements on four or five of the eight priority issues identified below will count among the most successful managers that the Department has ever had.