The World Trade Organization is often criticized for requiring its members to adopt policies which can detrimentally affect poor and vulnerable groups. Close analysis of the relevant provisions of WTO law, however, often reveals international trade obligations to be significantly more flexible than is commonly suggested. The author argues, however, that, on its own, detailed formal analysis of trade law paints an incomplete picture. Trade law also influences political choices by framing debates about trade policy – determining the arguments which can be made, who can make them, and in what forums they can be presented. The author illustrates this argument through a focused analysis of one controversy relating to the trade regime, namely the ‘GATS and water’ debate, and in particular the question of whether the General Agreement on Trade in Services may require the ‘privatization’ of water infrastructures.