We envisioned a new approach to controlling bulk supramolecular network properties by leveraging multiple supramolecular interactions in a nested configuration, such that the two interactions are not independent but dependent on each other (Figure ). In searching for a material to demonstrate this idea, we recognized that such a configuration could be achieved with MOC-crosslinked polymers (polyMOCs). MOCs are, in some cases, known to display pronounced host-guest binding ability, and a few reports of polyMOCs have leveraged MOCs that can bind guest molecules ; however, no studies have explored how the bulk properties of polyMOCs can be varied by altering guest binding thermodynamics, nor have they leveraged this unique nested junction structure to achieve functions that cannot be obtained with traditional supramolecular networks. For example, we imagined at least three functions that could potentially be uniquely achieved with nested polyMOC networks: (1) guest-induced manipulation of bulk stress-relaxation dynamics, wherein small molecule guests alter the metal-ligand coordination dynamics of the junction; (2) resistance to dissolution under off-stoichiometry network formation conditions or in the presence of competitive reagents due to synergistic stabilization of MOC junctions bound to guests; and (3) the ability to control both percolation (i.e., gelation) and dissolution using selective self-sorting of MOC junctions driven by guest recognition. Here, we realize the synthesis of a new class of polyMOCs containing acetylene-space Pd2L4 junctions and demonstrate each of the above functions, establishing nested junctions as a new design principle for supramolecular polymer networks.