This report focuses on the habitat of the charismatic - but critically endangered - Sumatran orangutan. It offers an overview of the many ecosystem services that the orangutan's forest habitat provides in Sumatra and how estimates for revenue from payments for ecosystem service schemes compare with revenue from other land-use scenarios. This report also aims to emphasize the strong link that exists between biodiversity, ecosystem services and human well-being, to raise awareness and to seek more careful management of natural resources.