Hydrogen production through water splitting appears to be the best solution in the long run for the storage of renewable energies. Hydrogenases are organometallic enzymes containing iron and/or nickel metal centers, whose catalytic performances rival that of platinum for hydrogen evolution. Their fascinating properties make them the ideal inspiration for the design of new molecular catalysts for technological devices. During this presentation, the bio-inspired strategy will be illustrated: How can this approach be at the origin of efficient systems that achieve H₂production in a catalytic manner? How can it provide useful information regarding the catalytic mechanism of the enzymes?