Surface Scattering Experiments with Conduction Electrons shows how this process can be used to investigate surface processes of thin metal films. Since a thin film is in one direction of a size comparable to the mean free path of the conduction electrons, such a film is both substrate and sensor and must be characterized by other surface-analytical methodsas demonstrated here. Also discussed is how the dc-resistivity measurement permits the study of surface processes such as adsorption, desorption, and surface diffusion up to crystalline growth. The in situ observation of epitaxial growth is additionally shown to be possible. Thus the electronic structure of superimposed metal films and superlattices can be elucidated. This is an essential topic for all surface physicists.