Modern armed conflict has taken a variety of forms and occurs at a variety of levels, raising serious questions concerning the relationship between the law of armed conflict and the reality of contemporary warfare. Many contemporary armed conflicts are fought in pursuit of unlimited objectives, whereas other modern wars seek to advance limited goals. While in some cases modern wars are fought by traditional armies composed of clearly identifiable soldiers, often modern armed conflicts are waged by guerrilla or partisan fighters whose identities are easily confused with non-combatants. Terrorism is increasingly a characteristic manifestation of this contemporary warfare. In the broadest sense, contemporary warfare has raised often controversial and vexing questions concerning the applicability of the law of armed conflict and, when applicable, the interpretation of its principles and tenets. This engaging volume addresses some of the contemporary normative and legal challenges and problems associated with the application of the concepts of just war, the just conduct of war, and the law of armed conflict to 21st century warfare.