Over 50 years ago the existence of surface-mediated interactions (Fig. ) has been proven experimentally. Since FOs influence surface charge distribution, it is no wonder they have attracted attention in this field. In fact, a theoretical prediction of FOs' involvement in this phenomenon has been published in the late 80-s. Interestingly, as early as in 1998 Wahlstrom et al. , have reported a STM picture of interference pattern produced by multiple adatoms (see Fig. ). This study has become the first experimental evidence of long-range surface-mediated interactions and hinted at the role of FOs. Since than in a number of studies FOs have been used to account for or explain surface-mediated adsorbate-adsorbate interactions or even adsorbate ordering. Fig. Materials surface chemistry's aim is to describe both types of adsorbate-adsorbate interactions: (i) indirect, that is mediated by the surface, and (ii) direct (through space).