On present day supercomputers, it is possible to screen thousands of materials in a "high-throughput" manner using density functional theory (DFT) with computationally efficient semilocal exchange-correlation functionals. However, DFT is a ground-state theory, which inherently cannot describe the excitedstate properties required for organic semiconductor devices. The excited-state properties of isolated molecules may be calculated relatively efficiently with time dependent DFT (TDDFT). Indeed, TDDFT has been employed for high-throughput screening efforts to discover organic chromophores. The properties of crystalline organic semiconductors depend not only on the molecular properties, but also on the crystal packing and the resulting electronic interactions between molecules. There is a vast body of literature reporting how changes in the crystal packing affect device relevant properties of organic semiconductors from excitedstate energies to charge carrier mobility. Therefore, for applications based on crystalline organic semiconductors it is important for computational materials discovery efforts to focus on predicting the excited-state properties of crystals as opposed to isolated molecules.