Operations research on the Ibadan Market-Based Distribution Project in Nigeria investigated the feasibility of a contraceptive distribution system using traders in the traditional markets to sell pills, condoms, and foaming tablets. Two hundred and thirty-five female and male traders were trained and supplied with contraceptives, malaria treatments, and oral rehydration salts to sell at low prices in 39 markets. This article presents findings from qualitative and quantitative research conducted in 1985-89 to determine if the sale of contraceptives in the marketplace is acceptable to participating traders and shoppers and to identify trader and market characteristics associated with sales volume. Sales of contraceptives totaled 18,286 pill cycles, 11,818 packages of four condoms, and 4,429 packages of four foaming tablets. The average monthly sale for each participating trader was 5.3 units. Adaptations of this model are being tested in other Nigerian cities and in Accra, Ghana.