The field of chemistry covered in this book covers all but two of the d-block transition metals in groups 5-10. More than 4000 compounds are discussed and about 2500 references are cited. Metal-metal bonds of orders 0.5 to 4 are found in these compounds. An extensive, critical review and discussion of preparations, reactions, bonding, and physical properties for all classes of compounds is given. The various chapters have been written by fourteen experts.