1. Compared to the general price of goods and services as measured by the consumer price index, the prices of retail roller and breakfast maize meal have declined by between 34 and 51% in the major urban markets of Zambia between 1994 and 2010. 2. Inflation-adjusted wholesale maize grain prices have also declined over this period but by a smaller amount. 3. Inflation-adjusted marketing margins between the wholesale price of maize grain and the retail prices of roller and breakfast meal have declined from 41% to 64% since the early 1990s when the market liberalization process began. Since the early 1990s, there has been substantial new investment in commercial maize milling as well as by the informal hammer milling industry. Enhanced competition at this stage in the maize value chain appears to have conferred important food security benefits to urban consumers.