Vibrant agricultural commodity exchanges will greatly enhance the performance of Africa’s agricultural sectors and contribute to overall economic development. Yet specific conditions in grain markets are required for agricultural commodity exchanges to develop.1 The absence or short-lived nature of many of these conditions explains why commodity exchanges for staple grains have remained stunted in Sub-Saharan Africa despite strong interest in their development by the international donor community and by most elements of the private sector. This study identifies these preconditions and assesses the scope for development organizations to support the sustainable development of commodity exchanges in eastern and southern Africa.