An OLED device comprising: a) a substrate; b) one or more OLED light emitting elements located on the substrate and including a first electrode formed on the substrate, one or more OLED light emissive layers located over the first electrode, and a second electrode located over the OLED light emissive layers; c) an encapsulating cover located over the second electrode and affixed to the substrate; and d) a thermally-conductive adhesive material in thermal contact with and adhering the OLED light emitting elements to the encapsulating cover over the light-emitting area of the OLED light emitting elements, wherein the thermally-conductive material is more than 1 micron thick and has a thermal conductivity greater than 0.25 W/mK.