Abstract: The present invention discloses a high speed apparatus for stacking books received from a delivery conveyer and accounting for the books and the operation of the stacker as part of a manufacturing data and control system. The apparatus is formed of an input conveyer system, a stacking region, sets of forks for intercepting a predetermined number of the books to form a stack, mechanical apparatus such as pairs of chains for moving the sets of forks in and out of the common pathway stacking region, and a real-time control device for controlling the timing and movement along the substantially common pathway of the sets of forks. The forks are in substantially the same dimensions of vertical attitude and horizontal plane when within the stacking region when each stack is being formed and the sets of forks could theoretically overtake each other during a cycle since they are in the above-noted substantially common pathway.