Populations living in urban areas are rendered vulnerable due to myriad inter-related factors including rapid and unplanned population growth, organised violence, environmental degradation, precarious livelihoods and resource pressures. These challenges are likely to grow given that the proportion of the world’s population living in urban areas is projected to increase to 70% by 2050 (IDMC and NRC, 2014; UNISDR, 2014). Over the past forty years the urban population in lower income and fragile countries has increased by 326% and currently nearly one billion people or a third of the developing world’s urban population live in slums (UNISDR, 2014). While urban vulnerability presents an enormous challenge, it is important to acknowledge that urban areas are growing at least in part because of the relative availability of economic, social and other opportunities vis-à-vis rural areas. Nonetheless, it is commonly agreed that there is a pressing need to reshape humanitarian and development interventions undertaken in the urban context so that they harness existing resources and work to support and transform these urban systems to prepare, withstand, and recover from shocks and protracted crises (Knox-Clark and Ramalingam, 2012; Pantuliano, 2012). Against this backdrop, legal systems can play a crucial role in both strengthening and, potentially, undermining the capacities of persons exposed to urban fragility and vulnerability arising from a variety of sources. Such systems operate at different governance levels; municipal, national, regional and international. While all the government levels are doubtlessly relevant, this article outlines the pertinent “international” legal frameworks in a manner that is sensitive to the particularities of urban crises, including high population densities, the reliance on critical infrastructure, as well the inability and/or unwillingness of public authorities to fulfil their roles in certain areas of cities such as informal settlements, disaster exclusion zones and areas controlled by armed groups. It does so by firstly providing an outline of the key international legal frameworks relevant to addressing both human-made and natural disasters. The legal frameworks explored from this perspective are international humanitarian law (IHL) and international human rights law (IHRL). Secondly, while cognisant that international law tends not to explicitly distinguish between urban and rural areas, some of the key issues that these bodies of international law encounter in the aforementioned urban settings are explored.