Microbes play an important role in our everyday lives. As agents of infectious disease, they cause untold human misery, yet their beneficial activities are manifold, ranging from the natural cycling of chemical elements to the production of food and pharmaceuticals. In this introductory text, the authors provide a clear and accessible account of the interactions among microbes, their environments, and other organisms, citing examples of both beneficial and detrimental activities. The book begins by considering positive activities, focusing on environmental microbiology and manufacturing, and then moves on to consider some of the more adverse aspects of microbes, particularly the myriad diseases to which we are susceptible and the treatments currently in use. Microbiology in Action will prove to be a valuable text for those studying microbiology.