<p>Integrated quantum photonics has become a burgeoning field of research that encompasses quantum light sources, nonlinear materials, photonic resonators, optical interconnects and detectors. There is also a growing need for programmable devices that enable rapid reconfiguration of individual components in integrated quantum photonic chips. In this Review we present our vision for programmable quantum photonics and explain why we regard it as the next frontier in the field of quantum nanophotonics. We discuss state-of-the-art reconfigurable and tunable elements (for example, phase shifters and quantum light sources) and highlight the emergence of materials that offer a new toolkit for tunability and control (for example, van der Waals crystals). Programmable quantum circuitry will play a pivotal role in transitioning quantum optics from proof-of-concept demonstrations to robust technological solutions for the second quantum revolution.</p>