There continues to be widespread interest in the applications of hydrogen as a clean fuel and its potential for local electricity production and use in transport. Recent years have seen a variety of breakthroughs in our understanding of the nature, structure, and biosynthesis of hydrogenases. This book is a timely description of these developments, taking a lucid, multidisciplinary approach. Scientists in fields, such as clean technology, biochemistry, electrochemistry, agriculture, and general biotechnology, will find this an accessible resource that brings together the many facets of these enzymes.