Bioethanol, one of the most promising technological advancements of the century, has been widely acclaimed for being produced from diversified origins. Production of bioethanol from food grains (as in Brazil or the United States) is however frequently criticized in the food vs. fuel debate. Several research studies across the globe, investigating the potential use of various renewable resources (such as waste biomass), have resulted in the emergence of second and/or third generation bioethanol processes. This chapter attempts to consolidate various aspects of bioethanol production from solid waste biomass. Waste biomass of lignocellulosic and starch-based origin, such as municipal solid waste, industrial waste (waste paper or coffee residues), livestock manure, and agricultural waste (wood biomass and agricultural crop residues), were reviewed for their potential to produce ethanol. This chapter describes the feedstock prospects, process technologies, and the current research and industrial developments.