Abstract: A heat sink for use with luminaires can be tightened securely against a lamp socket and can be loosened to allow the lamp socket to be rotated. The heat sink also contacts preferably an endplate or other structure of the luminaire having a preferably large amount of exterior surface area. Heat is drawn away from the lamp socket and interior of the luminaire via the heat sink to the endplate or other structure, where the heat is dissipated via convection into the surrounding air. By using another structure of the luminaire having a relatively large amount of surface area, the heat sink advantageously need not be large or bulky.