Abstract: One or more misaligned packaging blanks or blanks for cigarette boxes in a stack can be realigned by causing the stack to be engaged at both ends by two half-shell-shaped receiving portions. It is then tilted by 90.degree. so that the edges of the blanks all rest on a supporting surface. The two receiving portions are then brought together so as to realign any blanks protruding from the stack longitudinally. A detection device are incorporated in one of the receiving portions for checking the proper orientation of the stack and for causing it to be turned over one way or the other, depending upon its initial orientation.