Atmospheric corrosion is a complex process involving many variables including metal, atmospheric environment, and exposure conditions. Once the corrosion process has been initiated and a continuous film of corrosion products covering the whole surface of steel has been established, the kinetics of the corrosion process will be controlled by (a) the thickness of corrosion product layer, (b) their morphology (degree of compactness, crack network, etc.), and (c) the nature and distribution of the different phases. This work explores the potential of backscattered electron (BSE) imaging as a tool for the study of atmospheric corrosion. The sensitivity of the backscattered signal to small differences in average atomic number and variations in microporosity, allows study of the discontinuous nature of the atmospheric corrosion process and the distribution of contaminants in the corrosion product layers. Quantitative image analysis of BSE images has also been used to characterize the compactness of rust layers.