The International Energy Agency-Renewable Energy Technology Deployment (IEA-RETD) program released this study to shed light on the potential current and future supply chain constraints on deployment of wind and solar photovoltaic energy. The objectives of the study are risk assessment and risk management in the short and medium term. The authors identified 25 constraints on future deployment of wind and solar technologies, several of which could potentially be severely limiting, but they found that dozens of industry and policy measures could help mitigate potential supply chain bottlenecks. On the demand side, policies securing long-term demand can help balance that side of the supply-demand balance. On the supply side, future raw materials constraints can be overcome by switching to alternative, more readily available materials.