Abstract: A luminaire includes a housing, at least one core member coupled to the housing, at least one LED positioned on the core member, and at least one heat sink thermally coupled to the LEDs. The core member includes a first end, a second end, and a body extending from the first end to the second end. The body's outer surface includes one or more receiving surfaces spaced apart and operable to receive one or more LEDs. LEDs can be added, removed, or repositioned on the receiving surfaces to change the light distribution. The cooling system includes either an integral heat sink, an external heat sink, or both. The core member is designed to increase lighting efficiency by directing more light away from a direction opposite the intended area of illumination.