Communication: Thin film organic electrolumiscent devices based on poly(2,3-diphenyl-1,4-phenylenevinylene (DP-PPV, see Fig.) have been fabricated using the chlorine-precursor route. Devices with the configuration Mg/DP-PPV/ITO are shown to have an external quantum efficiency for green electroluminescence of 0.1%, a value comparable to the efficiency of Ca/PPV devices.