XPS and Auger spectroscopies are oflen used in several fields ofactivity of the steel industry that may be sorted into three items :defectology and expertise, research and development on productsand process, study of metallurgical mechanisms. In these fields ofactivity the results, that we provide our customers with, are obtainedwithin the frame of a "Quality insurance - Certification" approach.This approach is based on the appropriate measures taken byArcelor Research to give customers every confidence that any errorof measurement will be prevented. The few examples in this paperdemonstrate how XPS and Auger analysis, performed on samplesof small size to study phenomena at a nanometer scale, can be agreat help to the industrial line management.