Volume 35 of Reviews in Mineralogy defines and explore the topic of geomicrobiology. It is organized so as to first introduce the nature, diversity, and metabolic impact of microorganisms and the types of solid phases they interact with. This is followed by a discussion of processes that occur at cell surfaces, interfaces between microbes and minerals, and within cells, and the resulting mineral precipitation, dissolution, and changes in aqueous geochemistry. The volume concludes with a discussion of the carbon cycle over geologic time. Basis for this volume was the Short Course on Geomicrobiology presented by the Mineralogical Society of America on October 18 and 19, 1997, at the Alta Peruvian Lodge in Alta, Utah.