The life and work of the pioneering applied geochemist, Professor John Stuart Webb (1920–2007), FREng, founder and long-time Director of the Geochemical Prospecting Research Centre (1954–63) and Applied Geochemistry Research Group (1963–79), and Senior Research Fellow until 1988 is reviewed. The work began with his recognition of geochemical provinces as the key to location of areas which might contain mineral deposits, initially recognized in New Brunswick, proven in Zambia and Sierra Leone. The initial focus of the work was on mineral exploration but, with the passage of time, it broadened to embrace: multi-purpose geochemical mapping; agricultural and environmental geochemistry; the publishing of pioneering regional geochemical atlases of Zambia (Webb et al. 1964a), Derbyshire (Nichol et al. 1970b), Denbighshire (Nichol et al. 1970b), Devon and North Cornwall (Nichol et al. 1971), Northern Ireland (Webb et al. 1973) and England and Wales (Webb et al. 1978); applied marine geochemistry (especially the investigation of metalliferous brines and manganese nodules); and urban geochemistry. Over 100 students have now graduated with higher degrees from the school which Webb began, to apply the techniques in industry, geological surveys, or to train a new generation of exploration and environmental geochemists around the world. Sadly, the recognition which he well deserved was much greater abroad than in his home country. Following his retirement, research in environmental and marine geochemistry continued to prosper for another 20 years.