Drawing from the findings of the Stanford Task Force on Preventive Force, Abraham D. Sofaer offers a practical guide to identifying and considering the issues relevant to preventive uses of force, in the hope that such uses of force, if undertaken, will advance national and international security and the purposes of the United Nations Charter. The book examines such key questions as What are the dangers and limitations of relying on preventive force in dealing with security threats? When, if ever, would states be justified in using preventive force without U. N. Security Council approval? What standards and procedures could enhance the legitimacy of preventive force?The Best Defense? Legitimacy and Preventive Force reveals that, although preventive uses of force in general pose even greater dangers and potentially adverse consequences than uses of force in self-defense, the costs of each type of error depend on the consequences of acting versus not acting in particular cases. No general rule is available to ensure foolproof decisions. It makes sense, the author concludes, to encourage states to undertake a systematic appraisal of the merits of any threat or use of preventive force based on legal standards, U.N. Charter purposes, and established norms of conduct.