Abstract: In Dye Sensitized Photoelectrosynthesis Cells (DSPEC), separate half reactions for water oxidation or water reduction to H2, or the reduction of CO2 to carbon fuels, occur at separate electrodes. Significant progress has been made in the design of both types of electrodes based on nanoparticle semiconductor film electrodes. For water oxidation, modification of TiO2 electrode surfaces by core-shell structures, with surface stabilization by Atomic Layer Deposition (ALD), has led to relatively stable, efficient electrode structures with integrated combinations of molecular chromophores and catalysts including a step-by-step mimic of Photosystem II. At NiO electrodes, surface modification and the use of external molecular absorber-quencher pairs have been used maximize efficiencies and minimize back electron transfer. A new approach, based on surface-bound molecular assemblies, has also been used to prepare both photoanodes and photocathodes in integrated photoelectrochemical cells.