This book focuses on the chemistry (structure) and methods of formulation of biocides, and aspects of the chemistry that are important for different application areas. Biocides are categorized in the book by chemical categories such as alcohols, halogens, organic acids, and quaternaries and surfactants. Natural products are also covered. Each group or chapter includes inactivation mechanisms, synthesis, preparation, properties, stabilities, analysis, appropriate applications, formulations, toxicity, safety, regulation, and advantages and disadvantages. Information is provided in an easily accessible manner for all application groups. A biocides summary is included as an Appendix, which includes key biocides, their chemical structure, and their applications.