The physico-chemical character of a surface determines the behaviour towards external influences (representatively light reflexion and -adsorption, wettability, resistance, biological substances etc.) or their own influence on physico-chemical processes (such as catalysis or crystallisation). Therefore information about the chemical and physical structures of a surface layer is of immense importance for basic and applied research. Also innovative products are typically refined by a tailor made surface design, whereby such processes as well as the surface composition have to be controlled down to sub microscopic or even atomic level. Consequently the exact characterization of chemical, physical or morphological surface properties of materials is mandatory. Only modern methods of surface analysis grant access to these information.