Bioremediation is a soft bioengineering technique to clean up contaminated lands and soils using microbes, plants and earthworms. It is also a technique to stabilise the eroded lands and prevent soil erosion. Microbes are adapted to thrive in 'adverse conditions' of high acidity, alkalinity, toxicity and high temperature. Under favourable conditions of growth, microbes can biodegrade and biotransform the complex hazardous organic chemicals into simpler and harmless ones. Environmentalists are viewing microbes such as yeast, bacteria, algae, diatoms and actinomycetes as an 'eco-friendly nano-factories' for metal remediation. This book addresses these issues regarding the benefits of microbes, plants and earthworms in bioremediation.