All praises goes to God who has provided the grace to complete the project. The book will help the veterinary practitioners, researchers and especially students who feel to work on zoonotic diseases. The people who intended to study bacterial zoonotic diseases will get necessary information from the book. Though there are some limitations in organization of the book and diversified information, I've tried to collect and compile all the up-to-date information on brucellosis of different species including marine mammals. Finally, despite of my all efforts and means to make the text as accurate as possible, still there is likelihood of some errors in sorting through many thousands of bits of information. Any concerned veterinarian or researchers who has used this book and feels that it could be improved, please write to me with your comments and suggestions.