Multivalency describes the interaction between multivalent receptors and multivalent ligands. It plays a pivotal role in biochemistry, particularly in protein–carbohydrate interactions, both in solution and at interfaces. At interfaces in particular, multivalency is often poorly understood in a quantitative sense. Research on multivalency is currently an interplay of the fields of biochemistry and supramolecular chemistry. On the one hand, the understanding of supramolecular interactions at interfaces provides a tool for the quantitative description of multivalency at interfaces. On the other hand, the multivalent design rules developed in biological chemistry are applied in novel supramolecular nanostructures. The current review focuses on the former perspective (i.e. the use of well defined supramolecular platforms that function as model systems for understanding multivalent phenomena at interfaces).