KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility, workers watch the progress of the Multi-Purpose Logistics Module Leonardo as it moves across the building to the Cargo Element Work Stand that Raffaello recently vacated. The payload canister was a temporary location during the switch. At right is the MPLM Raffaello, temporarily occupying the Element Rotation Stand formerly holding Leonardo. Three MPLMs were built by the Italian Space Agency - Donatello, Leonardo and Raffaello - to serve as a reusable logistics carrier and primary delivery system to resupply and return cargo requiring a pressurized environment to the International Space Station.