This article is a summary of four different aspects of soft x-ray spectroscopy that are being used or developed by our group to probe the interface. The first is to study the change in valence band fluorescence emission by mimicking a high density of interface atoms through the use of a multilayer. The second method uses an intense localized excited state to characterize the buried interface. The third uses Raman scattering to probe changes in band structure produced by stoichiometric changes in the valence band density of states for atoms at the interface. Finally, a method to study interface atoms by using valence emission from interface atoms that are excited by x-ray standing waves is being developed.