The World Bank’s Partnership for Market Readiness (PMR), through grant support and technical assistance, supported 23 emerging economies and developing countries in building their institutional and human capacities to design, institute, and implement carbon pricing instruments, such as emission trading systems, carbon taxes, and or carbon crediting mechanisms along with underlying infrastructure such as monitoring, reporting and verification (MRV) and registry systems. As the PMR winds down and its successor - the Partnership for Market Implementation (PMI) - becomes operational in 2021, the time is opportune to take stock of and analyze key lessons learned from the decade of PMR experience. This report draws lessons from the PMR’s decade-long country, technical work, and policy analysis work programs and relates the insights captured through its extensive country participant consultation process, its online surveys, and feedback from its contributing country partners and World Bank task teams. The lessons documented in this report are expected to provide practical insights for other developing countries planning to design and implement carbon pricing initiatives. In addition, the lessons learned on the PMR process, as well as the grant implementation process, are likely to help similar initiatives, including the PMI, to adopt improved program design and governance options that support efficient funds allocation, deployment, and implementation.