Abstract: A grid system for supporting a plurality of individual panel members generally in the same plane. A grid is formed of a plurality of structural beams or grid members which are disposed in intersecting relationship to each other in a predetermined geometric relation. More specifically, the grid system is adapted to be suspended from the superstructure of a building and includes a plurality of spaced, parallel grid members. Each pair of such grid members are adapted on their opposite sides to support the marginal edge portions of ceiling panels while the adjacent sides of each pair of grid members are appropriately spaced and formed to receive an outlet portion of an air handling conduit for conveying conditioned air from a plenum-like structure disposed between the grid system and the overhead building superstructure into the room below the grid structure.