The Rotterdamsche Droogdok Maatschappij (RDM) was the largest pre-World War II shipbuilding and repair company in Rotterdam in the Netherlands, existing from 1902 to 1996. It built 355 mostly major seagoing vessels, 18 of which were submarines. During its existence, the wharf operated 12 floating docks and in its heyday employed 7,000 people at one time.