Abstract: Cargo containers are moved between a dock and a ship by a crane which has a vertically movable landing platform, a waterside trolley for moving cargo between the ship and the landing platform, and a landside trolley for moving cargo between the dock and the landing platform. The landing platform is moved to different elevations to change the extent of vertical movement performed on the cargo by each of the tolleys. In the course of operations, the landing platform is movable to an elevation which corresponds approximately to the higher of: (a) the elevation of the designated location on the ship where the article of cargo is to loaded or unloaded, or (b) the elevation of the highest obstacle between the dock and the designated location; and, both trolleys are operated while the landing platform is at this elevation.