This 4th, revised edition of Bacterial Fish Pathogens fills the need for an up-to-date comprehensive book on the biological aspects of the bacterial taxa which cause disease in fish. Since the 3rd edition was published in 1999, much has changed in the control of disease of farmed and wild fish. Many more scientific articles about bacterial fish pathogens have been published, describing such new pathogens as Pasteurella skyensis, and antimicrobial compounds for the control of disease have been replaced by alternative methods, such as the use of probiotics. This updated book analyses all the new information, including that on new pathogens and new developments on long established diseases, such as furunculosis and vibriosis. Consideration is given to all of the bacterial taxa which have at some time been reported as fish pathogens, whether they are secondary invaders of already damaged tissue or serious, primary pathogens.