Metalloproteins, which contain metal atoms at their active sites, are involved in many biological processes. Nearly half of all proteins require the presence of a metal atom to function, and thus, the metalloprotein is a new hot focus of chemical biology and biomedical science. This review volume addresses the most exciting current research on metalloproteins & metalloenzymes, according to their functional category. It hereby thoroughly devotes developments on substance synthesis, signal transduction, gene regulation, drug metabolism, redox catalysis, catalytic hydrolysis, metal trafficking, metal sensoring, rational metalloprotein design, and current approaches for metalloprotein studies. Every functional metalloprotein chapter highlights a series of metalloproteins with structural, functional and mechanical aspects. It is not only a review volume of the most exciting developments of metalloproteins, but also a book encompassing nearly all aspects of the current metalloprotein research field.