Despite international commitments to reduce the current rate of biodiversity loss at the global, regional and national levels by 2010, recent evidence indicates that biodiversity continues to be lost at a terrifying pace. This publication, produced jointly by the World Bank, IUCN (the World Conservation Union) and the Nature Conservancy, sets out guidance on the use of economic valuation methods, which have been developed to value ecosystems and the services they provide, as well as the costs of conservation.