The supply structure of inland waterway transport market in Germany is essentially dominated by few shipping companies, such as Imperial, Rhenus Partnership, Haeger & Schmidt, Lehnkering and the Deutsche Binnenreederei, which in most cases have emerged from formerly company-owned shippers. Some larger shipping companies, as well as many small independent owner operators (private shippers with up to three boats) complement this supply structure. Charterers do not own their own shipping space but merely organize ship transports on behalf of senders. They could be called forwarders for inland waterway transport. The role of shipping companies has changed significantly. While traditionally their responsibilities included the organization of shipping space, the provision of freight, and the disposition and implementation of transport, they primarily only assume the role of shippers nowadays