This chapter presents the international humanitarian law (IHL) framework for humanitarian relief during armed conflicts and complex emergencies. It sets forth the main rules of IHL governing humanitarian assistance in international armed conflicts, including situations of occupation, and in non-international armed conflicts. In particular, it highlights contemporary challenges to the delivery of humanitarian relief in situations where non-state armed groups control territory. The chapter also analyses the question of to what extent the IHL framework applies in situations of complex emergencies, i.e. in situations where armed conflict and other man-made or natural disasters coincide on the territory of a party to an armed conflict. It examines the relationship between IHL and international disaster law in such circumstances as well as the question to what extent the two fields of law can complement each other. This chapter argues that in complex emergencies, the applicable legal framework is primarily IHL, which constitutes a legal regime that is specifically tailored to conflict situations. It also provides greater protection for civilians than, for example, in the ILC Draft Articles on the ‘Protection of persons in the event of disasters’.