To provide a sheet stacking device for stacking sheets of generally rigid material.

This sheet stacking device includes at least one gripper device operable to releasably grip an edge of a sheet material and gripper drive means operable to move the gripper device from a first location to a second location. A support device supports the sheet as the sheet moves from the first location to the second location. The support device has a supporting position, wherein the support device supports the sheet and a non-supporting position wherein support for the sheet is removed. A stacking platform is provided below the second location. Control means control the gripper device, the gripper drive means and the support device. The control means causes the gripper device to grip an edge of the sheet at the first location, the drive means to move the gripper device from the first location to the second location, the gripper device to release the sheet at the second location, and the support device to move from the supporting position to the non-supporting position, dropping the sheet onto the stacking platform.