Non-covalent interactions are one of the key topics in modern chemical science. These inter- and intramolecular weak interactions (e.g., hydrogen, halogen, and chalcogen bonds, stacking interactions and metallophilic contacts) have a significant effect on the properties of polymers. In this Special Issue, “Non-covalent interactions in polymers”, we tried to collect fundamental and applied research manuscripts (original research articles and comprehensive review papers) focused on non-covalent interactions in polymer chemistry and related fields. The scope of the Special Issue is very broad: we welcome all the contributions that deal with the synthesis, structure, functionality and properties of polymer systems involving non-covalent interactions.