The hallmark of supramolecular chemistry is the design of molecular materials and structures that exhibit useful properties resulting from the collective interaction of different molecular components. Our research focuses on understanding molecular interaction and self-assembly in solution and on surfaces in order to control molecular crystallization and assembly of complex multicomponent systems. We utilize synthetic, physical-organic, and supramolecular approaches to generate and study 3-D coordination polymers—called metal-organic frameworks, or MOFs—featuring a range of architectures with high internal surface areas and void volumes. These porous MOF solids serve as host materials that actively absorb and store organic guests. My group currently is exploring strategies to incorporate photoactive and catalytic components into MOFs with the aim of creating novel, highly stable, heterogeneous catalysts. For example, we have shown that environmental contaminants such as aromatic hydrocarbons readily are absorbed and efficiently oxidized by photosensitizing MOFs, demonstrating the utility of such materials for applications in environmental remediation. We also are investigating the influence surfaces play in promoting molecular crystallization on surfaces as a means to control polymorphism (crystalline forms) and resolve racemic chiral drugs via crystallization on chiral and achiral organic templates.