There is growing awareness that important environmental transformations are catalysed, mediated and influenced by microorganisms, and geomicrobiology can be defined as the influence of microorganisms on geologic processes. This is probably the most rapidly growing area of microbiology at present, combining environmental and molecular microbiology together with significant areas of mineralogy, geochemistry and hydrology. This volume focuses on the function of microorganisms in the environment and their influence on 'global' processes. It will include state-of-the art approaches to visualisation, culture and identification, community interactions and gene transfer, and diversity studies in relation to key processes. This overview for researchers and graduate students will represent environmental microbiology in its broadest sense and help to promote exciting collaborations between microbiologists and those in complementary physical and chemical disciplines.