The discovery and evolution of oranometallic cluster chemistry is a major event in the development of inorganic chemistry. This is the second volume in the series 'The Chemistry of Metal Clusters' edited by Du Shriver, Herb Kaesz, and Richard Adams.

This volume focuses on the chemistry of the early transition elements in their lower and middle oxidation states, i.e., halide, sulfide, oxide, phosphate, alkoxide, and related o-donor ligands. The key feature linking all these complexes in metal-metal bonding is the presence of pi-donor ligands.