This volume represents the state of the art in the field of soil bioremediation. It summarizes the microbiological fundamentals of aerobic and anaerobic degradation mechanisms of bacteria and fungi for all substance groups relevant in contaminated soil as well as of plant mechanisms to eliminate organic and inorganic substances by phytoremediation. It also presents all techniques developed since more than one decade to commercially solve the problems of contaminated sites by biological processes. Furthermore, it gives a survey on future developments and trends in overcoming soil decontamination problems by using near-nature methods called natural attenuation or intrinsic bioremediation.