The aim of this title is to document the meeting exploring the key challenges in understanding the biological chemistry of metals. State of the art work using advanced physical and computational methods to probe the electronic structure and the reactivity at the active sites of metalloenzymes is discussed. These investigations are truly interdisciplinary and the development and application of physical methods and computational chemistry to biological problems require spectroscopists and theoretical chemists to collaborate with each other and with a wide range of other scientists, notably biochemists and coordination chemists. This is particularity true as spectroscopy and theory typically prove insight into slightly different aspects of reactivity. The book will provide substantial benefits to both experimentalists and theoreticians working in this filed.