Cape Town is one of the wealthiest cities in the Southern African region. Yet, the vast majority of households in poor areas of the city experience food insecurity. This paper uses AFSUN data to examine the characteristics and drivers of food insecurity in Cape Town. While food insecurity correlates closely with income poverty and household structure, broader factors also impact upon urban food security, most notably urban design and market structure. Efforts to address urban food insecurity should therefore not simply target the household. Instead, a food systems approach is necessary, which considers supply chains, procurement, nutrition support programmes, public health, environmental sustainability, water and waste, the support of local enterprise and so on. Furthermore, this approach must consider the geography of the urban food system, in particular planning and zoning regulations regarding the location of both formal and informal food retail within low-income areas of the city.