The direct conversion of solar energy into fuels, H2 in particular, at a simple and low cost semiconductor/water junction is still a challenge. Despite the theoretical simplicity of such a device, limitations in suitable semiconductor materials have hindered its development. Recently, few authors started exploring the potential of organic and hybrid organic-inorganic semiconductors, as an alternative to the usual transition metal oxides or more costly III-V semiconductors, in photoelectrochemical systems. Most reports described performances in the order of 1 mA/cm2 at the reversible hydrogen electrode potential (RHE), relatively low onset potentials and limited stability. Here we report our recent results on the optimization of a hybrid organic-inorganic photocathode for the direct conversion of solar light into chemical energy. Starting from a prototypical P3HT:PCBM blend as photoactive element, we focused our attention on different interfacial layers their influence on the photocathode performances. The photocatalityic activity and long-term stability of a simple, catalysed, bulk heterojunction is proven and the effect on hydrogen generation performances of properly engineered selective contacts is investigated separately. Introduction of an electron selective layer is found to increase the photocurrent response while the key point is the introduction of suitable hole blocking layer which shifts the onset potential towards positive voltages allowing operation in a electrical region compatible with a tandem photoanode and/or a PV cell. The relevance of our findings can be summarized in few key points: (i) high performances with a maximum photocurrent of 8 mA/cm2 at RHE and 50% IPCE; (ii) optimal process stability with 100% faradaic efficiency along the whole electrode’s lifetime; (iii) excellent energetics with onset potential as high as +0.7 V vs RHE; (iv) promising operational activity of several tens of hours and (vi) by-design compatibility for implementation in a tandem architecture. Collectively, this set of features establish the hybrid architecture we developed well ahead of existing reports on organic photoelectrochemical systems and suggest the potential of the hybrid organic-inorganic photoelectrochemical (HOPEC) concept as real contender to the traditional inorganic counterpart.From the knowledge learnt, we anticipate that stable operation at photocurrents close to the maximum achievable with OPV, beyond 10 mA/cm2 at positive bias, are achievable. This work opens up the way to the exploration of the rich library of organic semiconductors developed for OPVs in photoelectrochemistry and to the realization of a new generation of large area, solution processed tandem water splitting devices for renewable and low cost direct conversion of solar energy into hydrogen.