Abstract: Covalent organic frameworks (COFs) are nanoporous organic materials with a two-dimensional sheet-like architecture. These materials offer precise control over various molecular properties such as pore size, functionality, and architecture and are promising for applications including separations, water treatment and remediation, energy storage, and catalysis. However, realizing the potential of this novel class of materials requires addressing fundamental challenges related to processing, stability, and molecular design. For example, most COFs are produced as insoluble powders that are difficult to mold or incorporate into applications. Furthermore, COFs can exhibit poor stability and lose both porosity and crystallinity in the presence of polar solvents. Finally, while they are generally highly conjugated structures, their optical and electronic properties remain poorly understood. Here, I discuss the relationship of COFs to other macromolecule and present recent advances in the synthesis, processing, and stability of COFs. I will demonstrate how COFs can be processed to produce porous and crystalline thin films and demonstrate recent findings related to the fragility and stability of COFs under different environmental conditions. I also present work on the application of COFs for separations and photochemical degradation of molecular targets. This work demonstrates that COFs are a promising class of macromolecules with attractive properties for a broad range of applications.