Abstract: An apparatus for sorting of equal length records with the sorting time maximally overlapped by the time taken for loading and unloading of records. The minimal structure consists of a decision mechanism linked to and associated with a network of ladder structures. The activity within the network is so synchronized that the sorting activity in most ladders occurs while some ladder within the network is still undergoing the loading of input data; and during the unloading phase, the individually sorted data from each ladder are merged concurrently to produce a sequence of sorted records. The overlap between sorting and loading varies from 0 for records requiring no loading/unloading, to 100% for multi-ladder networks with loading/unloading.A single ladder structure supporting a type of transposition sort is first described both in a full exchange scheme and a fast version. Then, the mechanism for loading/unloading equal length records to the single ladder is set forth.