Developing countries face considerable disadvantages in trade disputes with their more powerful and wealthier counterparts. Nonetheless, Benin, Burkina Faso and Mali successfully challenged US cotton subsidies, a watershed event in international trade relations. This article explores how the West African governments and cotton farmers confronted US policy, why they succeeded, and the campaign's likely implications. Drawing on interviews with representatives in West Africa and Geneva, public statements, documents filed with the World Trade Organisation (WTO), media coverage, and materials from non-governmental organisations, I analyse the behaviour of four key actors behind this initiative: cotton farmers, producers' unions, governments and the international financial institutions. Tactics included using the WTO's trade-dispute mechanisms, deploying many spokespeople with common messages, enlisting powerful allies, and using the media. The West African campaign is an example of politically weak countries effectively exploiting the liberal economic principles of multilateral institutions to challenge protectionist policies in the industrialised world.