Introduction to Microbial Hydrocarbon Production: Bioenergetics -- Diversity and Taxonomy of Methanogens -- Hydrogenotrophic Methanogenesis -- Ecophysiology of Acetoclastic Methanogens -- Methanogenesis from Carbon Monoxide -- Environmental Constraints that Limit Methanogenesis -- Methanogens: Syntrophic Metabolism -- Methanogenesis in Soils, Wetlands, and Peat -- Methanogenesis in the Digestive Tracts of Insects and Other Arthropods -- Methanogenesis at High Latitudes -- Methanogens and Methanogenesis in Hypersaline Environments -- Metagenomics of Methanogenic Communities in Rice Paddy Rhizosphere; the Importance of Methanocella -- Metagenomics of Methanogenic Communities in Anaerobic Digesters -- Anaerobic Digestion as Key Technology in the Bio-Based Economy -- Oxic Methane Cycling: New Evidence for Methane Formation in Oxic Lake Water -- Contribution of Methane Formation and Methane Oxidation to Methane Emission from Freshwater Systems -- Diversity and Taxonomy of Aliphatic Hydrocarbon Producers -- Alkane Biosynthesis in Bacteria -- Oil and Hydrocarbon-Producing Bacteria.-.