Polyoxometalates constitute an extensive class of compounds with an unmatched range of structures, properties, and applications. This book incorporates contributions from polyoxometalate scientists, and presents a summary of research developments in this dynamic field. It provides an introduction for academic and industrial chemists, biochemists, structural biologists, surface scientists, mathematicians, and others interested in new applications and devices. Topics discussed include synthetic strategies leading to functionalized organic polyoxometalate derivatives, oxothioanions, and supramolecular assemblies; solution equilibria pertinent to the bleaching of kraft pulp; molecular growth from discrete anions to framework materials, nano-devices and thin films via self-assembly processes; energy transfer solid-state optical and magnetic properties, selective homogeneous and nanocluster-based catalytic applications; photocatalytic decontamination of water resources; and structural crystallography of the ribosome.