Written by leading authorities, this unique work examines the aqueous chemistry of vanadium. Focusing on the V(V) oxidation state, it highlights the use of 51V NMR spectroscopy. It covers reactions of vanadium with biologically important ligands such as amino acids, peptides, and sulfhydryl ligands. It reviews vanadium’s role in biological systems and pharmacological effects and addresses the importance of ligand electronic properties in determining speciation, coordination geometry, and heteroligand reactivity. It also describes recent advances in practical applications such as in the non-aqueous vanadium oxide bronze battery systems, which are particularly suited to medical applications.