Abstract: An HID lamp assembly has a relatively small envelope size enabling use of the lamp assembly in aircraft applications as well as other applications. The lamp assembly comprises a reflector, a discharge lamp mounted to the reflector, and a ballast which controls the delivery of power to the discharge lamp. The ballast is mounted to and carried by the reflector, at least partially surrounds a base of the discharge lamp, and is axially aligned with the reflector. The transverse dimensions of the ballast are less than the corresponding dimensions of the reflector at a wide front end thereof.