The transboundary diagnostic analysis of the South China Sea and its associated catchment areas, is a process that focuses on identifying water-related problems and concerns, their socio-economic root causes, and the sectoral implications of actions needed to mitigate them. The analysis further seeks to determine those issues which have transboundary, i.e. involves more than one country, causes and/or impacts, appropriate mitigation of which will have to be done on a regional or bilateral basis. The analysis then becomes the basis for a strategic action program which is coordinated both at the national and regional levels.