Nanowires offer exciting opportunities in quantum optics. Using quantum dots in semiconducting nanowires, we demonstrate the generation of single photons as well as pairs of entangled photons. Making electrical contacts to semiconducting nanowires, we make a single quantum dot LED where electroluminescence from a single quantum dot can be studied. Superconducting nanowires also offer application in quantum optics: we demonstrate efficient single photon and single plasmon detection with superconducting nanowire single photon detectors. I will also address quantum circuits where quantum light sources, circuits and detectors are all combined on a chip.