Sargeson is distinguished for his sustained and original contributions to elucidating the mechanisms of inorganic reactions. His studies during the past 10-15 years have been central in raising inorganic synthesis from the doldrums of random ad hoc procedures by the disciplined and systematic application of fundamental mechanistic principles. His work on the mechanism of the base hydrolysis reactions of cobalt (III) has been definitive and leads directly to a new and deeper understanding of the likely mechanisms for reactions such as amino acid ester and peptide hydrolysis in carboxypeptidase A. He was among the first to appreciate the significance of the chiral coordinated amine centre for integrating synthesis with stereochemistry and mechanism through configurational relationships between reactant and product. His ensuing applications of inorganic conformational analysis to chemical and biological specificity have been pioneering. He is an international authority in his field.