Many countries including the US, Japan, Australia, Korea and others are now actively developing emissions trading systems. Europe has accumulated a rich experience with designing and implementing a cap and trade program, and policy makers elsewhere have an opportunity to look at this experience on key issues that continue to challenge consensus. Foremost amongst these are issues surrounding allocation, costs and competitiveness. This report examines the experience of the European Union’s Emission Trading System and suggests key lessons relevant to current debates in many regions, with associated recommendations.