Brief synthesisHome to more than 800 species of fauna and located in northeast Thailand, Dong Phayayen-Khao Yai Forest Complex (DPKY-FC) covers 615,500 hectares and comprises five almost contiguous Protected Areas; Khao Yai National Park, Thap Lan National Park, Pang Sida National Park, Ta Phraya National Park, and Dong Yai Wildlife Sanctuary. The complex spans 230 kilometers from Ta Phraya National Park on the Cambodian border in the east and Khao Yai National Park at the western end of the complex. The Dong Phayayen-Khao Yai Forest Complex, with its high annual rainfall, acts as a critically important watershed for Thailand, draining into and feeding five of the country’s major rivers: Nakhon Nayok river, Prachin Buri river, Lamta Khong river, Muak Lek river, and Mun river. Criterion (x): The Dong Phayayen-Khao Yai Forest Complex (DPKY-FC) contains more than 800 fauna species, including 112 species of mammals, 392 species of birds and 200 reptiles and amphibians. More than 80% of Khao Yai National Park remains covered in evergreen or semi-evergreen forest, with much of it tall, good quality primary forest.