My work over the past 20 years has been directed to the geology and mineralogy of sulphide ore deposits. In particular, I have aimed to analyse and interpret mineral assemblages, mineral chemistry and textural evidence to understand the genetic history of mineral deposits, and to discover controls on element partitioning, paragenesis and mineral stabilities. The approach has encompassed major, refractory mineral phases (e.g. pyrite), as well as the trace components such as sulphosalts and tellurides. Studies have been applied to deposits ranging from volcanic-hosted and SEDEX-type massive sulphides, epithermal precious metal, porphyry and skarns, and even liquid-magmatic Cu-Ni-PGE deposits. My research has often been of a generic character, i.e., common problems are applied to deposits across the world and across geological time, rather than to specific deposits or ore provinces.