Hybrid polymer–nanocrystal photovoltaic (PV) cells have received much attention during the past decade as promising low-cost solar energy harvesting devices, and showed significant progress with power conversion efficiency reaching 5 % recently. This review starts from the introduction of hybrid materials to their application in electronic devices, with particular focus on bulk-heterojunction hybrid polymer–nanocrystal PV devices. The synthesis, surface chemistry, and electronic properties of colloidal inorganic nanocrystals are described. The recent development of hybrid PV devices will be discussed from the perspective of tailoring both inorganic nanocrystals and conjugated polymers, controlling polymer–nanocrystal hybrid morphology, engineering polymer–nanocrystal interface, and optimizing device architecture. Finally, future directions for further advancing hybrid PV technology to potential commercialization are also discussed.