Coordination cages with specific architectures can be rationally designed by judiciously selecting metal nodes and organic panels with specific structural features. For metal ions, these characteristics include valency, coordination geometry, and the nature of ancillary ligands, and for panels -size, shape, and the number and spatial orientation of the donor atoms. The architectures of coordination cages determine their applicability in catalysis, separations, and site-selective derivatization of the encapsulated guests, among other functions. An important characteristic is the size of the largest window, which determines how readily the guest molecules can enter-and escape from-the cage's cavity. For example, hosts whose windows are small (compared to the guest size) can efficiently stabilize molecules that would otherwise undergo decomposition.