The recent EC–Biotech case highlights the emerging regulatory divide between WTO Members and reveals a deepening crisis over issues of science and governance in the world trading system. This article focuses on the potential role that social science expertise might play as an analytical tool in understanding trade disputes involving scientific expertise relating to matters of risk assessment and polycentric decision-making. Particular consideration is given to the paradigm of ‘post-normal’ science, which pertains in situations where competent national authorities have to frame and implement policies before all the (scientific) facts are known. As the amicus curiae brief by a group of five social scientists before the EC–Biotech Panel demonstrates, where there is a high degree of scientific uncertainty, as in the case of GM products, post-normal science can offer a valuable means of framing the dispute in a broader societal context than the sound science approach, which is used to assess health, safety, and environmental risks under the SPS Agreement.