The developing world today is challenging conventional accounts of city growth and change. In Africa, for example, conflict and mass displacement are reconfiguring the urban landscape in ways that are hard to ignore. This paper analyzes how conflict and the arrival of a large humanitarian aid infrastructure influence the dynamics of city growth and bring about a distinct spatial structure, niche gentrification, and informal economy in Nyala, Darfur. Using data from a three-year field study, we show how the size and socio-spatial organization of the city changed, the directions in which the city grew, and the factors that drove these changes. We look at interaction patterns between residents of Nyala itself and those now residing in internally displaced person (IDP) camps on the edge of the city. We show that considerations of both insecurity and risk are vitally important to understanding the processes of conflict urbanization. Conflict generates a distinctive social structure as internal displaced people, international aid workers, and long-time urban residents all move within the city.