Compliance with sustainability initiatives has become a virtual "prerequisite" for producers to access many mainstream markets in commodities sectors. These private voluntary systems can make important contributions to sustainable development, if the benefits of participation are fairly distributed between regions and supply chain actors. This paper uses a Global Value Chain framework to analyze how sustainability standards affect the distribution of economic benefits along international supply chains in the coffee, fisheries and forest products sectors. It examines how certification systems affect international trade flows, the generation of economic rents, and the accrual of costs and price premiums at different value chain nodes to determine where and by whom substantive economic benefits are enjoyed. The paper pays particular attention to impacts on commodity producers in developing countries.