Nearly ten years back the first edition of this book was ably published by the present publishers. In the intervening period systematic ichthyology has advanced very rapidly new discoveries of taxa, new areas previously unexplored and new concepts of taxonomy and new classification of the existing families, genera and species were brought to light. Many foreign ichthyologists undertook surveys in difficult areas and contributed much knowledge. The all catfish species inventory was funded by the US National Science Foundation which helped in new discoveries. Several changes have been incorporated especially in Siluriforms composition. A few genera have been merged, some families reoriented. In India The Zoological Survey of India undertook preparing faunal composition of several rivers, wildlife sanctuaries and several states. In some universities fish taxonomic studies and surveys of nearby streams and water bodies yielded many new discoveries and also new records. The National Bureau of Fish Genetic resources prepared a data base of freshwater fishes. A new line of genetic studies has thrown light of new knowledge of species composition and many closely related species have been recast. The Zoo Outreach organization, Coimbatore helped in preparing an endangered species of fishes by arranging workshops involving university scholars and research scientists. Thus the interval of ten years was very productive and improved our knowledge of freshwater fish fauna not only of our country but also the neighboring countries as Bangladesh, Pakistan, Myanmar, Nepal and Sri Lanka. The result is that 1042 species are now known as against 853 previously listed in the first edition. Most of this new knowledge may not be available to all and this second edition should prove to be useful aid. Moreover the illustrations published in 39 plates with colour photos of fish species would prove a helpful tool.