The applicability of international humanitarian law requires the existence of an armed conflict that is either international or non-international in character. Accordingly, the concept of armed conflict (as well as the related notion of war) and its temporal and material limits are the focus of the reprinted essays which open this volume. Subsequent articles address highly contentious issues regarding the relationship between the jus in bello and international humanitarian law on the one hand, and the jus ad bellum and international human rights law on the other, as well as the closely related principle of the equal application of international humanitarian law. In the light of contemporary conflicts, essays consider the legal position of States that have chosen not to become a party to an ongoing international armed conflict (law of neutrality) as well as the question of whether and to what extent international humanitarian law provides rules governing counter-terrorism operations, that is, the 'global war on terror'. Taken together, these essays provide a comprehensive analytical survey of the scope and applicability of international humanitarian law.