We feel that there is an urgent need to develop FO theory (covering long-range oscillations) that can be readily interfaced with existing approximate quantum chemical methods (such as DFT covering complex local electron density changes due to impurities). Such theory can be then used in hybrid quantum mechanical/molecular mechanical calculations (QM/MM), where the MM part is covered with new FO theory. We note that starting from the original Friedel description 1 , modern physical methods have made a qualitative leap and rely on the Green's function formalism to model FOs. Unlike the partial-wave Friedel approach, the latter provides a much more compact analytical solution. The Green's function approach is taking its rightful place as a powerful tool to predict and model surface interactions to gain insights into the origin of cooperative catalysis and surface chemistry. This will be a presiding theme of a series of articles we are about to publish.