The main aim of the entire book was to develop a biological process for the treatment of the textile industrial effluent. This book based on biological decolorization of Dye by Serratia marcescens. An attempt has been made to optimize conditions for the efficient decolorization and the exploitation of the micro organisation for Dye removal. Emphasis on the application of modern research to practical problems for environmental issues to give proper prospective on the development of new method for controlling pollution.