Two-component systems are signaling pathways that regulate many bacterial characteristics, such as virulence, pathogenicity, symbiosis, motility, nutrient uptake, secondary metabolite production, metabolic regulation, cell division, and many more. These systems regulate physiological processes in response to environmental or cellular parameters and enable adaptation to changing conditions. They are also potential targets for anti-microbial drug design. In recent years, significant advances have been made in the understanding of the role of two-component systems, and molecular studies have uncovered basic mechanisms of signaling. In this book, expert contributors from around the world present the current knowledge on two-component systems in bacteria and critically evaluate the vast amount of exciting new information that has been brought to light in recent years. The book covers various topics, including: the structure-function analysis of two-component systems * the sensing mechanisms * essential or atypical two-component systems and signaling networks * two-component systems in stress responses * two-component systems in developmental processes * two-component systems in virulence and symbiosis. The book provides a comprehensive overview for graduate students, academic scientists, and researchers in the pharmaceutical industry. This major reference work is essential reading for everyone working on bacterial regulation or anti-microbial drug design and is a recommended volume for all microbiology libraries.