This book reviews the latest advances in the bioelectrochemical degradation of recalcitrant environmental contaminants. The first part introduces readers to the basic principles and methodologies of bioelectrochemical systems, electron-respiring microorganisms, the electron transfer mechanism and functional electrode materials. In turn, the second part addresses the bioelectrochemical remediation/treatment of various environmental pollutants (including highly toxic refractory organics, heavy metals, and nitrates) in wastewater, sediment and wetlands. Reactor configuration optimization, hybrid technology amplification and enhanced removal principles and techniques are also discussed.