The light-driven synthesis of fuels requires efficient coupling of photon absorption with bond-forming chemical reactions. Molecular photoelectrocatalysis is an emerging approach in solar fuel production based on single molecules that support electrochemical hydride formation and photochemical bond-forming fuel synthesis. This Perspective article outlines the design requirements for transition metal candidates and describes the development of the first molecular photoelectrocatalyst for dihydrogen (H2) evolution. Mechanistic aspects are discussed in the context of electronic tuning of the catalyst, and the outlook for future development is considered.