During the 1970s, society began to become concerned with the general state of health of the environment. Widespread releases of contaminants, either accidental or purposeful, into soil systems ranging from surface soils to deep aquifers have mobilized both engineers and scientists into a search for technology that will effectively clean up contaminated soils at a reasonable cost. Biotechnology has been harnessed for centuries by man for the performance of beneficial functions that have greatly enhanced our standard of living. As the thrust of cleanup efforts intensified during the 1980s, technologists once again turned to microorganisms for a solution to the world-wide problem of contaminated sites. The potential of bioremediation is almost boundless. Tremendous strides have been made over a relatively short time, both in the discovery of novel biochemical mechanisms and the development and/or refinement of innovative reactor designs. Unfortunately, rarely do opportunities exist for environmental scientists, research engineers, and engineering practitioners to meet and discuss issues facing development of bioremediation techniques from interesting bench-scale experiments through to fully developed fielded technology with supporting design protocols. Engineering Foundation Conferences provide such an opportunity for informal and unhindered critical evaluation of the state-of-the-art of the different aspects of engineering technologies. The papers presented in this publication are a selected few that exemplify the exciting and stimulating discussions that occurred over the four days of the Engineering Foundation's First International Symposium on Bioremediation of Surface and Subsurface Contamination held in Palm Coast, Florida. The papers range from basic research to case studies on successful applications of biotechnology for site remediation. The authors of these papers represent leading experts on various aspects of the technology. Contributors were invited from various domestic and foreign professional entities including universities, governmental agencies, industries, consulting firms, and commercial vendors. This mix of professional background afforded interesting and at times conflicting viewpoints on issues hindering increased usage of biotechnology for site remediation. The papers presented do reflect these differences in opinion and approach to development of biotechnology and its application. It is through discussions and publication of such viewpoints that a better understanding of bioremediation (from the petri dish to the 100,000-gallon or bigger reactor in the field), and of the technical and political impediments to further progress. We hope that you enjoy and benefit from the reading of these papers as much as we have enjoyed working with such a distinguished group of experts.