In a sorter-finisher distributing sheets ejected from a copying machine among a plurality of bins and thereafter stapling the distributed sheets, the plurality of bins can move independently from each other within a first area where the sheets are distributed and a second area where the distributed sheets are stapled. Some of the bins among which the sheets are not distributed are continuously moved to said second area without actuating a stapler, and then the other bins among which the sheets are distributed are moved to the second area one by one actuating the stapler. Further, in the sorter-finisher, a finishing mode which allows an operation of the stapler after a distributing process can be selected in the middle of or even after as well as before the distributing process.