Mountains of the world cover about one-fifth of the land surface, are home to one-tenth of the world's population, and provide livelihood to some of the poorest communities in the world. Mountain lakes and streams are a source of freshwater for countless riparian human communities, support industries, provide water for storages for irrigation and hydropower electricity production and for fish. Some countries situated in mountain areas are landlocked, with no access to marine fishery resources, hence the fish of lakes, streams, rivers and reservoirs are an important source of animal protein, always in short supply in mountain countries. The Fifty-third General Assembly of the United Nations declared the year 2002 the "International Year of Mountains". With the present document, that reviews the current status of capture fisheries and aquaculture in mountains of developing countries of Asia, Latin America, Africa and the Pacific, the FAO Fisheries Department contributes to the efforts of the United Nations to promote sustainable mountain development. While there are certain limitations of cold water fisheries, the recent success of developing aquaculture in mountain provinces of Viet Nam shows that fish farmers in the rural areas can become the direct beneficiaries of the implementation of inexpensive aquaculture technologies, and as a consequence achieve significant improvement in their standard of living. As fisheries play an important role in providing food and income to people in mountain areas, they must be integrated into the rural development and water resource development initiatives. Governments in some countries have already done so, but in a number of countries much still needs to be done. This document also provides a list of issues, some of which need to be addressed in some countries. As several problem areas are common and fishery resources, such as migratory fish stocks, may have to be shared among neighbouring countries in mountain regions, collaborative action on a regional scale may become the most cost-effective way to address common problems and share experiences. This can be achieved through action programmes for mountain countries. Therefore, this document concludes with a selection of activities for improving fisheries in mountainous developing countries.