Corrosion is a natural global problem of immense importance. Oxidation of iron and steel not only compromises the structural stability of a widely used and versatile material but it also creates an abrasive compound (iron oxide) that can score the surfaces of metals, rendering them useless for the purpose for which they were designed. Clearly, the identification of corrosion in its nascent stages is a high priority for reasons that range from aesthetics to economics. Many bacteria in the facultatively aerobic genus Shewanella have the capacity to respire some metal oxides, such as iron oxide, by way of a variety of oxide-binding proteins lodged in their outer membrane. In this study, a rapid, cost-effective system for the specific early detection of a variety of oxidized steel surfaces is described, taking advantage of bacteria with natural affinities for iron oxides, to identify the sites of nascent corrosion.