In order to protect the sea environment on the earth, any countries in the world have to cooperate together. The United Nations are playing a leading role to make international efforts. Examples are the United Nations Convention on the Law of the Sea and International Convention for the Prevention of Pollution from Ships.

　On the other hand, some environmental problems are specific to the smaller scope of the sea – a regional sea- , and countries around the regional sea are very likely to share the cultural and social backgrounds. Therefore, it would be effective that neighboring countries take their own actions to protect their common marine environment in the region. Based on this idea, the United Nations Environment Program (UNEP) launched the Regional Seas Programme in 1974. This is an international program to be implemented regionally beyond borders in order to control marine pollution and manage resources in marine and coastal areas in enclosed waters. The world ocean was divided into some regions, and neighboring countries have developed plans and institutionalization. In the Agenda 21 adopted at the Earth Summit of 1992, it was endorsed significance to promote the Regional Seas Programme considering environmental characteristics, regional, cultural and social backgrounds.

　Until now, 13 regional seas including the Northwest Pacific Region have established and started the Regional Seas Action Plans. One regional sea - Southwest Atlantic Ocean- is in the process of formulating. In addition, 4 regions including the Baltic Sea in the Northern Europe have carried out their own activities by setting out independent Regional Seas Programs from the UNEP.

　The objectives of the Regional Sea Programme are to define the comprehensive measures addressing the environmental degradation in the regional seas, and to manage and develop the marine and coastal environment based on the environmental quality and assessments of causes of the environmental deterioration.

　The Regional Seas Programme addresses not only consequences but also causes of the environmental deterioration. It is an action-oriented program to manage the marine and coast areas. Various activities have been promoted based on the Regional Seas Action Plan developed in each Regional Seas Protramme.

　The Regional Seas Action Plan is consisted of "Environmental Assessment," "Environmental Management," "Environmental Legislation," "Institutional Arrangement," and "Financial Arrangement."