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Plants photosynthesize with light that falls within the Photosynthetically Active Radiation (PAR, 400-700 nm) and this limits the rate of photosynthesis of leaves in the shade. In an agricultural field, where crops are usually grown in dense canopies, this is a severe loss factor for crop growth. In recent years, several cyanobacteria have been discovered that can perform oxygenic photosynthesis with near infrared (NIR, 700-800 nm) light that falls outside of the range of PAR. Their capacity to do so proves that it is possible to split water with photons of lesser energy, breaking the long-held paradigm of the scientific community that the fundamental energetic limit for this process was linked to the energy of the photons on the red edge of PAR. These discoveries have therefore sparked the idea of introducing these capabilities into plants, which – as discussed – would be especially beneficial for growing crops in dense canopies. The central goal of this research was to lay the groundwork for creating plants that, like these cyanobacteria, are proficient in far red photosynthesis. To start, we discuss which strategies several oxygenic photosynthetic organisms already use to harvest far-red light. Then, in more detail we have investigated the molecular mechanisms of light-harvesting of a particular antenna system that is capable of harvesting the far red and which is synthesized under low-light conditions during the so-called LoLiP response in some cyanobacteria. Using Cryo-electron microscopy we elucidate the unique helical shape of this antenna system, which we call far-red light allophycocyanin (FRL-AP). Using ultrafast transient absorption spectroscopy we show that excitation energy transfer between different FRL-AP subunits occurs within less than a picosecond. By using structure-based modelling of the transient absorption data it could be inferred that excitation energy diffusion between the low energy subunits should however be slow in FRL-AP, possibly m