Phage therapy refers to the therapeutic usage of bacteriophages to treat and manage pathogenic bacterial infections. Bacteriophages are a type of virus, which attaches to the bacterial cells and injects their genome in the cells. The viral genome replaces the bacterial genome and stops the bacterial infection from spreading. The bacterial cell responsible for causing the infection is not able to reproduce and new phages are generated as a result. Phages are selective towards those bacterial strains against which they are effective. They are commonly bacterium-specific, which makes it important to get a swab and culture it before initiating a treatment. Phages can also be applied topically or orally on the infected wounds, can be spread on the surface or can be utilized while surgical procedures are underway. This book provides significant information to help develop a good understanding of phage therapy. It presents researches and studies performed by experts across the globe. The extensive content of this book provides the readers with a thorough understanding of the subject.