Ions are nearly omnipresent in chemistry and biochemistry. By providing the highest intermolecular interaction energies, ionic interactions have an extreme impact on molecular structures, which are the key to molecular functions. Experimentally determined structures of small contact ion pairs in solution are very rare and sometimes lacking in complete research fields. In addition, despite the amazing progress in theoretical and supramolecular chemistry, the subtle interplay of interactions in small organic ion pairs remains largely unknown. As a result design principles for small organic ion pairs in solution are not available. To solve this general problem there is an urgent and actual need of the synthetic community, because ion-pairing catalysis is the actual hot topic in asymmetric catalysis. There, new catalysts have to be screened with high effort in a black box mode and reviews state that structural and mechanistic studies will be an essential part of the further progress in the field. In previous projects spread over the fields of organometallic, bioorganic, supramolecular and medicinal chemistry as well as transition metal catalysis and organocatalysis, we gained special NMR expertise in the structure elucidation of ion pairs and reaction intermediates as well as the assessment of intermolecular interactions. Now in this project, nearly all of these various techniques and approaches will be combined in a new and so far unprecedented way and complemented by techniques used for protein ligand interactions and extreme low temperature measurements. With this unique combination, NMR approaches will be developed and applied to elucidate the structures of catalytically active ion pairs and their intermediates in solution and to dissect their intermolecular interactions. The resulting detailed design concept for small ion pairs in solution will revolutionize not only ion-pairing catalysis but all scientific fields working with organic ion pairs in solution.