Abstract: Apparatus for binding stacks of sheets has two spiral or comb or the like binding devices located respectively at two binding stations. The stacks to be bound are fed by a conveyor to a distributing station from which the stacks are distributed alternatively to each of the two binding stations by a gripper assembly. The bound stacks are transferred from the binding stations to finishing stations by pivoted arms. After the finishing operation, e.g. the trimming and turning in of the ends of the spiral, the bound stacks are pushed by plungers to form a stack of books or pads at a common discharge station from which the stack is removed by a conveyor belt.