Helicobacter pylori is one of the most common infections in the world, and while most of those colonised by H. pylori will remain symptom free, about 20% of them may develop serious gastroduodenal disease including peptic ulcers or gastric cancer. H. pylori is the only bacterium linked to the development of cancer and consequently it is an important focus of research. Moreover, H. pylori may be related to a wide range of extra-gastrointestinal disease such as coronary heart disease, stroke, migraine, rosaceae and gall bladder disease. And, although the incidence of H. pylori infection is falling in industrialized countries it remains an important pathogen globally and as the prevalence of antibiotic resistance increases, the eradication rate of the organism is falling with a consequent failure to cure the ulcer disease. Against this background, this new work sets out the pathology, clinical presentation and options for treatment of H. pylori infection. An important reference not only for clinicians but also microbiologists, it provides in a single volume an uptodate summary of our current knowledge of this organism and the many ways in which it impacts upon public health in all parts of the world.