Photocatalytic hydrogen generation is considered to be attractive due to its combination of solar energy conversion and storage. Currently-used systems are either based on homogeneous or on heterogeneous materials, which possess a light harvesting and a catalytic subunit. The subject of this review is a brief summary of homogeneous proton reduction systems using sacrificial agents with special emphasis on non-noble metal systems applying convenient iron(0) sources. Iridium photosensitizers, which were proven to have high quantum yields of up to 48% (415 nm), have been employed, as well as copper photosensitizers. In both cases, the addition or presence of a phosphine led to the transformation of the iron precursor with subsequently increased activities. Reaction pathways were investigated by photoluminescence, electron paramagnetic resonance (EPR), Raman, FTIR and mass spectroscopy, as well as time-dependent DFT-calculations. In the future, this knowledge will set the basis to design photo(electro)chemical devices with tailored electron transfer cascades and without the need for sacrificial agents.