Abstract: The reciprocating grate according to the invention for the treatment of bulk material, particularly for cooling hot material by means of gases, comprises a plurality of rows of grate plates disposed behind one another in the longitudinal direction of the grate, of which at least some are moveable to and fro relative to the others, wherein the grate plates of rows of adjacent grate plates overlap each other somewhat like scales. In order that the wear between grate plates moving relative to one another and the requirement for confining air between these grate plates can be kept relatively low, in at least one longitudinal portion of the grate in each case at least two rows of grate plates which are immediately adjacent to one another are jointly movable relative to at least one succeeding row of grate plates.