The evaluation of corrosion damage remains one largely based upon conventional "macroscopic" test methods i.e. weight loss, polarisation methods etc. These methods assume that the material is corroding "uniformly" over the whole surface area. Where the anodic and cathodic sites of a corrosion cell are fixed on a surface, localised corrosion ensues which can lead to material failure, often in a very short time span. Recognition of this phenomenon has resulted in numerous attempts to spatially characterise corrosion activity. This in turn has lead to the development of Electrochemical Scanning Techniques, where a surface is scanned in the x and y axis producing a visual 2 dimensional corrosion activity map.