A new hi erarchy-preservi ng hi erarchi cal compactor which can be used with either 1D or 2D leafcef1 compaction techniques has been devel oped.The compactor is applicable for hierarchical layouts which consist of a number of arrays of identical cells. The hierarchy is maintained throughout the compaction process so that all the instances of a subarray of identical cells have the same shape after compaction.Currently a hierarchical compactor based on the suggested simplified graph model has been developed and experimental results on several benchmark examples show that the proposed method is satisfactory.