Solar energy is rapidly becoming a more important aspect in today's energy systems, and solar cells are playing a major role in this shift. However, to further boost the efficiency of conventional solar cells, fundamental thermodynamic limits must be overcome. Photon fission and photon fusion, also known as photon downconversion and photon upconversion, are gaining increasing attention as a means to improve solar energy harvesting in solar cells by overcoming thermalization and transmission losses, respectively. Important developments in these fields include the use of organic–inorganic hybrid materials that can leverage the advantages of each material. In this review, we look at the development of organic–quantum dot (QD) hybrid materials and their use as components of photon fission and fusion systems. We put a particular focus on the triplet energy transfer across these organic–inorganic hybrid interfaces and how this understanding has been developed. In the later part of the review, we focus on the recent examples of these hybrid materials as crucial components in solar energy harvesting applications based on triplet–triplet annihilation photon upconversion or singlet-fission–based photon multiplication. By highlighting the most relevant discoveries toward understanding and designing organic-QD hybrid interfaces for photon fission and fusion applications, we establish a starting point for researchers to continue moving this research field forward toward practical applications.