Gasification provides an excellent overview of current technologies for the gasification of coal, oil, gas, biomass and waste feed stocks. Starting from the basic theory, it reviews the potential feed stocks and their suitability for different types of gasification process. Commercial and near-commercial processes are described individually and various features discussed in detail. There is a comprehensive review of contaminants in synthesis gas as well as of gas treating processes. Gasification, the key technology enabling the production of biofuels from all viable sources--some examples being sugar cane and switch grass. This versatile resource not only explains the basic principles of energy conversion systems, but also provides valuable insight into the design of biomass gasifiers. The author provides many worked out design problems, step-by-step design procedures and real data on commercially operating systems. After fossil fuels, biomass is the most widely used fuel in the world. Biomass resources show a considerable potential in the long term if residues are properly handled and dedicated energy crops are grown.