This paper argues, on the basis of empirical evidence and the conceptual evolution over the years of what constitutes technology transfer, that much can be done within Environmental Goods and Services (EGS) and other areas of World Trade Organization (WTO) negotiations. This would, however, imply rethinking the mandate of EGS negotiations and steering the focus away from simply increasing market access for EGS to one that recognises and facilitates the importance of knowledge transfers including “tacit” knowledge embodied in services.