This article considers the ways in which insulin is currently deployed as a teaching context and points to areas where the accuracy or completeness of current approaches are open to question. The scientific processes underpinning the development of successive insulins (animal, bio-engineered 'human' and bio-engineered analogue) are identified, and the key roles of the wider social, ethical and commercial contexts of the developments are described. The account indicates some ways in which this topical subject could be used to reinforce current specifications and enhance teaching about the processes of science.