This volume brings together all the fishes that have been recorded from Sri Lanka's inland waters. A total of 62 purely freshwater fishes (including 29 endemic species), 26 brackish water or marine vagrants recorded from freshwater, and 21 exotic species now established in Sri Lanka are described. Many of them are rare, and three are described for the first time. Part 1 introduces the geography and hydrography of the island and its freshwater habitats. Part 2 deals with the zoogeography and conservation of the fish, and Part 3 consists of a series of articles presenting the species.