1 Environmental and Economic Aspects of the West Philippine Sea Angel C. Alcala 1 and Alberto A. Encomienda 2 1 Silliman University Angelo King Center for Research and Environmental Management, Silliman University, Dumaguete City 6200 email: suakcrem@yahoo.com 2 Former Ambassador, Republic of the Philippines and former Head of Maritime and Ocean Affairs Center, Department of Foreign Affairs, Philippines Abstract The West Philippine Sea includes the Luzon Sea as well as the waters around, within, and adjacent to the Kalayaan Island Group (KIG) and Bajo de Masinloc also known as Scarborough Shoal. The KIG is part of what is referred to as the disputed Spratly archipelago. Our estimate is that the KIG or the Spratlys are about 281,000 km 2 in area. The South China Sea has been studied in the past by the Indochina Institute of Oceanography, the Nha Trang Institute of Oceanography of Vietnam and probably also by other agencies. The latest to make joint oceanographic studies in the area were the Philippines and Vietnam. The present paper covers the geological history of the South China Sea, the Spratlys and the Palawan Island group including parts of Mindoro and Panay Islands and their rifting from the Asian continent in the past; the physical environment of the Spratlys, including the islands, shoals, and atolls and current systems in the South China Sea; the biological resources with emphasis on the coral reefs systems and the status of fish and fishery resources; the economic values of reef and pelagic fisheries; the connectivity of the biodiversity resources of the Spratlys with the Philippines and other countries; the disturbances in the area that could have a negative impact on the sustainability of fisheries and marine biodiversity; and finally recommendations on ocean governance policy and programs needed for the maintenance of the integrity of the sea environment and its resources especially no-take marine reserves and transborder peace parks. These parks, which have been proven useful in some marine areas of the world can be instruments for cooperation for research and development in areas that are claimed by several countries. These recommendations pertain to cooperative protection and management of the