Synopsis Composting is the biological decomposition and stabilization of organic substrates under conditions that allow development of thermophilic temperatures as a result of biologically produced heat to produce a final product that is stable, free of pathogens and plant seeds, and can be beneficially applied to land. Composting is one of the best method of recycling to improve soil fertility as well as disposal of organic wastes to check environmental pollution and health hazards. Manipulating moisture content, pH, nutrient concentration, and oxygen can bring about increased decomposition rates and change the characteristics of the compost. Techniques have been developed to produce plant nutrient enriched organic bio fertilizer which can form an important input in Integrated Plant Nutrient Supply (IPNS) system and organic farming. Earthworms may also play a significant role in composting of animal dung mixed with leaf litter and grosses in shallow and small-sized windrows or heaps. This book provides comprehensive account of composting technology.