This concise history of the major military reforms in the Soviet Union in the twentieth century fills an essential gap in scholarly studies on the subject and provides a model for analyzing past and future doctrine, force structure and technology, and command and control tactics. This study should be a benchmark for measuring and identifying reforms in three key periods. It is intended for historians and analysts in military affairs; political scientists; and scholars dealing with Soviet, Russian, and the new independent states in the region. This invaluable history analyzes three periods of fundamental reform. The Frunze reforms of the mid-1920s laid the institutional basis for the Red Army, enabling it to develop into an integrated and professional army. The post-World War II reforms and the process of demobilization and mobilization permitted the Soviet Union to remain a nation under arms without hobbling its economy. The revolution in military affairs in the Krushchev era illustrated Soviet accommodation to technological changes in warfare. And finally, the process of reform and imperatives for reform are evident in the Gorbachev programs of perestroika and glasnost, which were cut short. The case studies are made against a backdrop of external and internal politics and economics. Currently the centralized Soviet structures are disintegrating along lines by which they were developed earlier. Whatever the future, military reform and reorganization will relate closely to past practice. There are many similarities between past and present challenges and many lessons to be learned.