In the late 1990s, the British anti-genetic engineering (GE) movement effectively closed Britain's market for genetically modified foods, while the U.S. anti-GE movement had a negligible impact. In seeking to explain the different outcomes of these similar social movements, the authors draw upon the global commodity chains (GCC) literature to extend the understanding of the economic and industry-related openings and closures social movements face as they seek to promote social change. This analysis not only illustrates the importance of economic structures and organization for movement outcomes, but also shows how the economic sphere is culturally constituted. In this fashion, it broadens the social movement literature's understanding both of the way that political economy matters to movement efficacy and of the way that cultural processes infuse the economic sphere. The study advances the GCC literature by showing how GCCs are cultural as well as economic constructs.