During the early steps of photosynthesis, the solar photons are first converted into excitation energy, at the very spot they are absorbed, and this excitation energy is transported across the membrane towards the reaction centers where energy is stabilized into the form of a charge separated pair. In limiting light conditions, every photon reaching the photosynthetic membrane is converted into a charge separated pair, although the whole system is highly disordered. This can happen only if every step has been carefully optimized so to counter the disorder effects. In the last decade, new concepts have emerged which, at least for part, may explain how the quantum efficiency of this process can be kept close to unitY.