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The south and southeast Asian region is undergoing rapid growth both in its economies and its human populations. Fish is a popular item of diet in most countries of the region, and in many it is the major source of animal protein. The combination of increasing personal incomes, growing populations, and government policies aiming to enhance nutritional standards by raising per capita consumption of animal protein, result in a steeply increasing demand for fish. Satisfying the ever-rising demand is difficult at a time when most marine fisheries resources are perceived as being already fully, in some cases even over-exploited. Thus no major sustainable increases in production from marine capture fisheries can be expected. Similarly, large inland fish resources suitable for exploitation by commercialscale fisheries are also generally fully utilized. Indeed, catches from some major freshwater fisheries are actually falling drastically. This applies especially to yields from rivers, where human activities have had negative impacts on the aquatic environment. In addition to direct pollution from industrial and municipal sources, changing land use in the catchments (especially deforestation and destructive agricultural practices like slash-and-burn methods) has reduced the water retaining capacity of the hillsides, culminating in more frequent and intense flashflooding. Land erosion is also greatly accelerated, resulting in elevated suspended solid loads in runoff water which in turn increase the rate at which lakes, reservoirs etc. silt up. Growing economies and populations constantly demand more hydro-electric power, water for irrigation to increase agricultural production, and water for industrial and domestic use. For these purposes, many reservoirs have been created on Asian rivers by the building of dams, and many more such projects are under construction or planning. Dams have the side-effect of blocking the migrations of fish, denying some species access to their spawning and/or feeding grounds. Regulation of a river normally also reduces the area of free-flooding land downstream of a dam. Such natural floodplain areas are vital as breeding and nursing grounds for many species of fish. At the same time, increasing human population in the river basins and the introduction of more efficient fishing gears have resulted in higher exploitation rates, amounting to overfishing in some areas. Though limited mitigation measures are increasingly being taken into account (e.g. construction of fish passes around dams for species capable of using them, and tighter regulation of polluting discharges) it would be unrealistic to expect any major reversal in the downward spiral of riverine fish communities. To fill the widening gap between fish supply and demand, most Asian countries have pinned their expectations on the development of aquaculture. This strategy has generally proved correct, and in many parts of the region production of fish farms now exceeds that from freshwater capture fisheries. The overwhelmingly predominant method of freshwater fish culture in the region is in earth ponds. However, in denselypopulated south Asia new land available for pond construction is becoming increasingly limited. Consequently rising fish yields are now fueled more by intensification of production from existing ponds (by use of additional inputs, especially feeds, and/or by integrated aquaculture methods) than by new pond construction. A wide range of government and internationally-assisted initiatives have helped the expansion of aquaculture in Asia, but in all countries of the region the industry is now largely performing well in private hands. Though pond aquaculture will continue to be the biggest contributor towards increases in freshwater fish output, there are other substantial potential growth areas which have so far been relatively neglected. Foremost amongst these is intensification in fish production from currently underutilized “small water bodies”. These include natural lakes, reservoirs, farm and village ponds, irrigation canals, perennial or seasonal water bodies in floodplain depressions etc. These resources are generally too small to be of interest to large commercial fishing operations, but they provide incomes and, most essentially, contributions towards the family diets of very large numbers of small-scale and subsistence fishermen. In particular, the potential for fisheries development in manmade water bodies is often overlooked or given only cursory consideration at the time of resource creation. For example, dams on rivers are built for power generation or irrigation. Only after filling of the resulting reservoir is thought given to the potential for fisheries. Fish yields from these water bodies can be improved by a number of management strategies which are considered in later sections of this paper. Recognizing the potential of such waters to increase fish yields and improve income and nutrition amongst rural populations, the United Nations Development Programme (UNDP) funded a study of their extent, current utilization for fish production, and prospects for enhancement of output in selected tropical and sub-tropical Asian countries. The study was conducted under TSS-1 (Technical Support Services at the Programme Level) funding, and implemented by FAO. The countries for inclusion in the study were selected on the basis of similarities in opportunities for improving inland fisheries production. They were Bangladesh, Cambodia, south China (Yunnan Province and Guangxi Zhuang Autonomous Region), Indonesia, Laos, Myanmar, Thailand and Viet Nam. A senior-international consultant, Dr. David Edwards, toured the eight countries over a five month period between February and August 1995. In six countries (Bangladesh, China, Indonesia, Myanmar, Thailand and Viet Nam) he was assisted by national consultants.