This book attempts to approach the topic of biodegradation of hazardous wastes in a holistic fashion. The issues of science, engineering and regulation are all addressed. As much as possible, both theoretical and practical considerations have been dealt with. Selection of bacteria for the specific purpose of degrading compounds is discussed at the bench-scale to the field level. Engineering theory as applied to growth on toxic substances is discussed. The legal issues are covered. There are also several examples of field studies indicating the current usage of biodegradation, both within reactors and in situ. The use of biodegradation is compared with other mechanisms of disposal, in terms of time limitations, degradation limitations and, perhaps most important, cost. Individual papers have been processed separately for inclusion in the appropriate data bases.