Abstract: A concealed, spring-loaded, slide hinge for mounting the light transmitting door to a luminaire housing. The slide hinge includes a hinge-slide member on each side of the door frame adjacent one end of the door and a hinge arm mounted on each of the slide members for sliding movement with respect thereto. A coil spring interconnects the hinge arm to the adjacent door frame end and urges the arm toward that end. Each hinge arm also carries a hinge pin thereon which pivotally mounts the slide hinge to the housing. When the door is opened, the spring urges the door away from the housing to permit the door to swing freely about the bottom edge of the housing while the pivotal connection is maintained.