Professor David Richardson is a bacterial biochemist who has discovered many novel aspects of respiratory processes in bacteria from soils, marine environments and the gastro-intestinal tract. His work has revealed the great adaptive flexibility of highly branched pathways of respiratory systems by the isolation, characterisation and functional analysis of their component electron transfer proteins and enzymes. One example is the remarkable ability of some bacteria to utilise extracellular metal-containing minerals as respiratory electron acceptors. Richardson solved the question of how electrons, generated by intracellular catabolism, can move out of the cell to these extracellular minerals through the discovery of outer-membrane insulated nanowire complexes that he termed ‘porin-cytochrome’ complexes. Richardson was formerly Vice-Chancellor and President of the University of East Anglia, UK, and was awarded the Fleming Medal for his work on bacterial ‘respiratory flexibility’, in which he identified new physiological functions for respiration in bacteria, and a Royal Society Wolfson Foundation fellowship to study the production and destruction of the ‘forgotten’ greenhouse gas nitrous oxide.