The world is becoming increasingly urban, and the phenomenon of migration from rural areas to cities is particularly prominent in the developing world. This movement is exacerbating the negative impacts of cities on the natural environment, with dire consequences. By focussing on informal settlements in the city of Cairo - the largest city in Africa - this thesis aims to explore ways of making the resource-deprived communities of this city more environmentally sustainable, without sacrificing their social qualities, and expanding the economic opportunities that are available. A combination of methods and tools are used for this purpose, ranging from green space analysis, non-prescriptive and adaptable uses and building designs, elements of the green economy, and community-led implementation. The outcome of this thesis, therefore, is a design model that offers sufficient flexibility that it can be applied to any new settlement in Cairo, but is also sensitive towards the local culture.