The search found 78 PES schemes were in operation, with 13 under development (Annex 2). Of these 78 schemes, 37 were focused on forest/ biodiversity, 28 were watershed-related, and 13 were water quality trading programmes. Many PES programmes are located in Latin America, but there are also numerous schemes in Europe and North America, particularly in forest/biodiversity programmes. It is unlikely that the literature review has identified all the PES schemes, which are in use in the UNECE region.