Aquaculture in Asia has a history of more than 2500 years. Asia is recognized as the leading aquaculture region in the world contributing 90 per cent of the total world aquaculture production in 1996. About 100 species of finfish listed in the FAO yearbook are cultured in this area. This may be attributed to environmental and social factors. Recently, economic prosperity allowed people to change their preferences on seafood consumption. Aquarium enthusiasts have the opportunity to keep ornamental fishes. So, aquafarmers diversified their cultured species while the aquarists imported more exotic species. Generally, freshwater finfish are the primary exotic species in Asia. However, owing to their high economic value and market demand, marine finfish and ornamental fish have played the principal role in diversification. Applications of biotechnology in aquaculture and domestication are other possible approaches that may yield new species for culture. Species diversification offers both biological and economic benefits.