Quadrennial Defense Review (QDR)

Administration report, released every four years, that is a crucial element in ongoing national security and military reforms aimed at identifying new threats and developing new strategies to combat those threats. In response to what critics perceived as the slow pace of reform at the Pentagon in the years following the end of the Cold War, the U.S. Congress passed the Defense Authorization Act in 1997. The Act mandates that each new administration conduct a comprehensive examination of the nation's defense strategy, force structure, force modernization plans, infrastructure, budget plans, and other elements of the defense program and policies. This is the Quadrennial Defense Review (QDR).

Each Quadrennial Defense Review must define current threats, suggest strategies to foil those threats, and propose the required military forces. The first QDR was the third major strategic reassessment of the force structure of the armed forces in a decade, following the base force assessment in the administration of President George H. W. Bush and the bottom-up review of the administration of President Bill Clinton.

According to the Defense Authorization Act, the pace of global change required a new and comprehensive assessment of the defense strategy of the United States and the force structure of the armed forces needed to meet the threats to the nation in the 21st century. Critics, however, charged that neither the first QDR nor the National Defense Review, a Congress-appointed independent body that evaluated the QDR, went far enough in challenging ingrained security policy. In particular, these critics were concerned about the need to fight two regional wars almost simultaneously and maintain the forces necessary to do so.