This volume in the Encyclopedia of Sustainability Science and Technology, Second edition, provides a comprehensive overview of how waste-to-energy power plants (WTEs) can be built within or near cities to transform the non-recycled residues of society into electricity, heat, and metals. With nearly one thousand WTE plants worldwide, waste incineration has become increasingly important as a means of closing the materials life- cycle loop. China leads in the beneficial use of these residues with about 30 new WTEs built in each of the last three years, and with plans for at least 300 more, one or more in each large city; also, more and more cement plants use "waste" materials as alternative fuels. Since currently all of these plants combust less than 20% of the available wastes, and the remainder ends up in landfills or dumps, this sector represents a huge market in the making. This comprehensive reference is suitable for readers just entering the field, but also offers new insights for advanced researchers, industry experts, and decision makers.