Surface hardening techniques are of importance for all practical applications where a hard surface is needed to resist wear, along with a tough substrate to resist the impact that occurs during operation. The advantages of the gaseous nitriding applied to iron/steel are nowadays widely recognised. The objective of the present work is to find a method to control the growth kinetics of the nitrided layers on different types of steels, in an industrial furnace. In order to study the kinetics of the nitrided layer growth, it is vital that the amount of nitrogen can be measured as well at the surface as in the nitrided layers. In the present work, Auger Electron Spectroscopy (AES) applied to a cross section of the surface layer is put forward as the most appropriate technique for this purpose thanks to its high lateral resolution. Hence, the second objective of this work is to investigate the possibilities to characterise the nitrogen distribution in the nitrided layers using AES. This study should be useful to anyone studying a(n) (industrial) surface hardening technique and especially to scientists who want to perform AES analysis in a quantitative way.