Abstract: A sorter for collating sheets into sets comprises a plurality of sheet-receiving bins defined by an array of movable plates 1-5, 5a and an indexing wheel 23 for indexing the input ends of the bin plates sequentially past a fixed feed throat 22 to align the bin openings in turn with the feed throat 22. Adjacent bin plates 1-5, 5a are relatively movable apart and together for varying the sizes of the bin openings and are interconnected to limit their maximum spacing. The bin plates are arranged in a fan-like array and are so mounted that their inner ends abut to define the maximum bin spacing.