The genus Borrelia, in the spirochete phylum, is not closely related to any other bacteria and has a highly unusual genome composed of a linear chromosome and multiple circular and linear plasmids that appear to be in a constant state of rearrangement, recombination, and deletion. The determination of the genome sequence of Borrelia strains has facilitated tremendous advances in understanding this genus at the molecular and cellular level, as well as the pathogenesis of Lyme disease and relapsing fever. In recent years, there has been an explosion of new insights into the molecular biology, genetics, physiology, and ecology of Borrelia and its tick/vertebrate life cycle. This research is of particular importance as the incidence of Lyme borreliosis continues to increase. Written by renowned scientists who have made seminal contributions to the field, this book is a comprehensive guide to the pathogenic Borrelia, providing researchers, advanced students, clinicians, and other professionals with an encyclopedic overview of the molecular biology of this important genus and the pathogenesis of diseases. Leading authorities have made contributions on topics such as Borrelia genomics, DNA replication, gene regulation, transcriptomics, proteomics, metabolism and physiology, cellular structure, motility and chemotaxis, genetic manipulation, evolutionary genetics, ecology, tick interactions, Lyme disease and relapsing fever pathogenesis, animal models, host response, detection, and vaccines. The volume is essential for anyone involved in Borrelia research and is strongly recommended for microbiologists, immunologists, and physicians involved in spirochete research, Lyme borreliosis, or relapsing fever. The book is a recommended reference volume for all microbiology libraries.