During the 2 decades preceding the Persian Gulf War in 1991, the U.S. Army went through tremendous reform and rejuvenation. In explaining this important case of military change, this paper makes four central arguments. First, leaders within military organizations are essential; external developments most often have an indeterminate impact on military change. Second, military reform is about more than changing doctrine. To implement its doctrine, an organization must have appropriate training practices, personnel policies, organizations, equipment, and leader development programs. Third, the implementation of comprehensive change requires an organizational entity with broad authority able to craft, evaluate, and execute an integrated program of reforms. In the case of the U.S. Army in the 1970s and 1980s, this organization was the U.S. Army Training and Doctrine Command (TRADOC). To an unprecedented degree, TRADOC was able to ensure that changes in personnel policies, organizations, doctrine, training practices, and equipment were integrated and mutually reinforcing. Fourth and finally, the process of developing, implementing, and institutionalizing complementary reforms can take several decades. While today's demands differ from those of the past, this report suggests questions that may be useful in thinking about change today. Knowing the answers to these questions would enable informed judgment about the prospects for the successful implementation of a program of reforms. The consequences, for good or for ill, could be quite significant in terms of resources, lives, and the national interest.