Industrial and agricultural activity throughout this century has led to considerable contamination of soil and groundwater resources by hazardous chemicals. The technique of bioremediation uses living organisms--usually bacteria and fungi--to remove pollutants from soil and water with minimal disturbance to these environments. This approach, which is potentially more cost-effective than traditional techniques such as incineration of soils and carbon filtration of water, requires an understanding of how organisms transform chemicals, how they survive in polluted environments, and how they can...