Abstract: A light emitting diode (LED) light source, a method of manufacturing an LED light source, and a method of cooling an LED source. The LED light source comprises: an LED source; and an enclosure surrounding the LED source; wherein a gas or gas mixture is filled within the enclosure such that the gas or gas mixture acts as a medium for heat transfer away from the LED source; and wherein the gas or gas mixture is chosen to provide an increased heat transfer from the LED source compared to air.