This study describes the EnergyEfficiency for Sustainable Development (EEfSD) action plan,to scale up energy efficiency operations in clientcountries. The EEfSD strategy comprises of interventions atthree levels: policy and regulatory, sector and sub-sector,and at end-use equipment and appliances. It is structuredalong four tracks: integrating energy efficiency withineconomic and sector work; mainstreaming energy efficiency ininvestment operations; improving internal operational,learning and analytic capacity; and monitoring, evaluation,and outreach. Priority focus is on countries with highestenergy intensities, where rapid growth of the energy sectoris expected and where total energy use is greatest.Implementation of the action plan will be guided by theEnergy, Transport and Water Department, and will requirecooperation and collaboration across the Bank Group, inparticular the regional operations units. This paperpresents the estimated incremental costs for FY07-09 whichhave been committed from energy trust funds and Bank budget.