International Finance Corporation (IFC)has successfully developed sustainable energy projects in anumber of emerging markets over the last decade. While eachintervention is tailored to its specific markets and theneeds of clients, in general the initiatives have focused onusing local financial intermediaries as aggregating agentsto stimulate investment in both energy efficiency andrenewable energy, thus reducing both client operating costs(and improving the clients' margins) and greenhouse gasemissions. This paper focuses on the sustainable energyfinance project IFC has developed in the Philippines and howauthor have leveraged more developed projects and ensured aone-IFC approach, the importance of focused research,listening to and being responsive to clients, andmaintaining flexibility and realistic objectives in theprogram design. This document is intended for IFC colleaguesresponsible for developing projects in various businesslines and regions, with particular relevance to thoseinvolved with either sustainable energy or local financialinstitutions. The lessons are presented with minimumtechnical jargon to make the message accessible to as widean audience of project/program developers as possible.