Surface condition control is particularly important in industrially processed materials, because apparently minor surface phenomena involving selective oxidation or low concentration element segregation can modify the surface reactivity and alter the material's response to downstream treatments. These phenomena, therefore, must be investigated by the most sophisticated simulation and surface analysis techniques, to ensure that accidental contamination is avoided. The paper reports on combined XPS, AES and SIMS spectroscopy to assess quantitatively the surface modifications taking place in Fe-based alloys during annealing treatments under various atmospheres. A new method has been developed from the equations initially put forward by Seah to assess element and compound surface coverage, based on experimental XPS peak intensities, computed inelastic mean free paths and atom densities. It has been applied successfully to annealed specimens made of Fe, Fe-0.5%Si binary alloy and ultralow carbon (ULC) deep-drawing steel. Copyright (C) 2000 John Whey & Sons, Ltd.