Forests play a crucial role in protecting watersheds, preventing soil erosion, maintaining the water cycle, and fighting climate change. Timber and non-timber forest products (NTFPs) are an important source of income and nutrition. But economic development and growing demand for food, energy and wood resources are putting increasing pressure on forests and landscapes, including in Vietnam which in 2010 became the first country in Asia to institutionalize a nationwide policy on Payment for Environmental Services (PFES). Suppliers of watershed protection; natural landscape beauty protection and biodiversity conservation for tourism; forest carbon sequestration and the reduction of greenhouse gas emissions through the prevention and reduction of deforestation and forest degradation (REDD+); the provision of the forest hydrological services for spawning in coastal fisheries and aquaculture; are entitled to payments. The following presents principles in designing effective, efficient and equitable PFES policy and its payments to the suppliers of forest environmental services - individuals, households, communities or organizations - from a decade of CIFOR research in Vietnam.