On the margins of the 2014 World Economic Forum in Davos, 14 countries launched plurilateral negotiations on liberalizing trade in so-called environmental goods. The mandate was to build on the Asia-Pacific Economic Cooperation (APEC) list of 54 green goods slated for preferential tariff treatment within that trading block. Participants in the Environmental Goods Agreement (EGA) negotiations face a fundamental and defining decision: will the final agreement aspire to create a living list of environmental goods, or will the list in the ratified agreement be final? The paper identifies basic ingredients that are needed for such a living list to function and offers concrete examples of ways in which those elements might be embedded.