Maize, sorghum, wheat, and groundnuts are the most important food commodities in South Sudan. Sorghum, maize, and groundnuts are the staple foods for the poor in most rural areas. Maize flour and wheat (as bread) are more important for middle-income and rich households in urban areas. Sorghum and maize are generally substitutable for one another but preferences are shifting towards maize over time, especially in the southern half of Southern Sudan. Groundnuts are important for the rural poor in Northern Bahr El Ghazal, Warrap, and Lakes states. Short-term sorghum is harvested in July – August in Greater Equatoria states and in September – October in Greater Bahr el Ghazal, Greater Upper Nile states and Jonglei states, and long-term sorghum in December – January particularly in Lakes, Western Bahr El Ghazal, Warrap, and Upper Nile states. Maize grain and flour from Uganda are available throughout the year because of the bi-modal rainfall pattern and carryover stocks. The main retail markets are in the state capitals, namely, Juba, Aweil, Malakal, Wau, Torit, Kuajok, Bentiu, Bor, Rumbek, and Yambio, but historical price data sets (2006-2010) are only available for Juba, Aweil, Malakal, and Wau only. The most important local wholesale market is in Renk, a mechanized cereal producing area in Upper Nile state. Aweil, Wau, Kuajok, and Bentiu are mostly supplied in cereals from Khartoum and El Obeid, while Malakal is also supplied by Renk through Kosti. In Juba, Torit, Bor, and Rumbek, cereal supplies mostly come from Uganda.