Recently, Zheng et al. developed the first OSC device above 20%, with a tandem OSC that reaches 20.2% . Although progress continues, the main issues that hinder the development of higherperformance tandem OSCs are finding suitable materials optimal for the interconnecting layers and active layers. While the interconnecting layer is vital for efficient charge transport through the device, the active layers are the limiting component for solar absorbance to reach the theoretical maximum PCE. A huge advantage of tandem cells is their ability to absorb multiple different regions of the solar spectrum. When the solar photons reach Earth's surface, a majority of the energy is in the UV, visible, and near-IR regions. Despite progress in development of many compatible donor/acceptor pairs, there is still a lack of materials that absorb the near-IR region. Since tandem OSCs have a minimum of four absorbers within the active layers, optimization of these devices is like finding matching needles in four haystacks. Each layer requires two complementary materials with respect to their energy-level alignment and solubility. Additionally, all four materials need to maximize the absorbance of the solar spectrum with minimal overlap to reach higher PCEs. With the size of the organic chemical space estimated of magnitude 10 60 , computational guidance is crucial for optimal material selection.