Microoganisms are distributed across every ecosystem, and microbial transformations are fundamental to the operation of the biosphere. Microbial ecology is the study of this interaction between microorganisms and their environment, and arguably represents one of the most important areas of biological research. Yet for many years our study of microbial flora was severely limited: the primary method of culturing microorganisms on media allowed us to study only between 0.1 and 10% of the total microbial flora in any given environment. Molecular Microbial Ecology gives a comprehensive guide to the recent revolution in the study of microorganisms in the environment. Details are given on molecular methods for isolating some of the previously uncultured and numerically dominant microbial groups. PCR-based approaches to studying prokaryotic systematics are described, including ribosomal RNA analysis and stable isotope probing. Later chapters cover DNA hybridisation techniques (including fluorescent in situ hybridisation), as well as genomic and metagenomic approaches to microbial ecology. Gathering together some of the world's leading experts, this book provides an invaluable introduction to the modern theory and molecular methods used in studying microbial ecology.