This 4th edition is divided into two parts: the first on principles and the second on practices. Part I begins with an historical overview, followed by descriptions of the types of antimicrobial agents, factors affecting efficacy, evaluation, modes of action and types of resistance. Also included is a new chapter on the problems of biofilms, as there are particular difficulties in inactivating sessile bacteria. Part II covers topics relating to sterilization and the control of these processes, including heat, radiation, gases and filtration. It also includes updated material on new and emerging technologies, discusses special problems in hospitals, dentistry and pharmaceutical practices, and concludes with an evaluation of the activity of agents and good manufacturing. The section relating to the spoilage of wood, paper, textiles, paints and stonework in the preservation section has been removed to ensure that this edition is focused on issues relating specifically to health and medicine.