The Bush administration’s decision-making process leading to the invasion of Iraq in 2003 has been singled out for its many shortcomings: failure of intelligence; lack of debate concerning options; an insufficient invading force; and poor postwar planning. Contrary to the administration’s claim that no one foresaw the difficulties of waging a war in Iraq, many concerns about the challenges the United States would face were raised inside and outside of government. Yet, none of this information had a significant effect on the decision-making process. This paper develops a decision-making model that integrates elements from the individual to the organizational level and explains how important information was marginalized, leading to a poor policy outcome. The model illustrates how the combined effects of the president’s formal management style, anticipatory compliance on the part of key players, bureaucratic politics, and the intervening variable of the 9/11 terrorist attacks contributed to a defective decision-making process.