Two-dimensional (2D) covalent organic frameworks (COFs) are periodic layered materials composed of organic linkers connected by covalent bonds. Due to high degree of porosity and large surface area, COFs are excellent candidates for a series of applications including gas storage and gas separation. Moreover, COFs have been reported to have promising application areas in sensing, proton conduction, catalysis, energy storage, light har-vesting, and electronics, owing to a high amount of π-electron conjugation in-plane and π-π stacking interactions, which facilitate exciton migration and dissociation, that can be further enhanced via tuning the donor-acceptor units. Vibrational spectroscopy techniques, such as infrared (IR) and Raman spectroscopy, are widely used tools for the characterization of 2D materials, including identifying contributions from different components of host-guest systems. Since 2D COFs, and 2D polymers are commonly syn-thesized through wet-chemical methods, any remaining solvent contributes signals, potentially complicating the interpretation of the spectra. It has been previously reported for 2D COFs that the presence of guest molecules can affect several properties including the stacking order and tensile strain. A recent study reveals that pristine COF-1 and COF-1 with trapped solvent (mesitylene) molecules inside its pores show varying degrees of stability under high-pressure, which can be monitored via Raman spectroscopy. Raman measurements are also employed to track reactions in solution. Some noteworthy examples include the in situ catalytic reaction monitoring of phthalocyaninebased conjugated COFs and metal-organic frameworks (MOFs) using in situ Raman spectroelectrochemistry.