Combined transport can be roughly divided into two important markets: seaport-hinterland transport and continental transport. Short sea transport can be regarded as a sub-form of continental transport.
The market segments differ in the way they function and in the handling units used to transport the goods. For example, only ISO containers are transported in seaport to hinterland traffic, whereas swap bodies and semi-trailers can be transported in continental traffic.
Port operators are the gateway to hinterland traffic. This is where the goods to be transported are transshipped and distributed to the respective modes of transport. They may also act as operators themselves, organising the main flow of goods through subsidiaries in rail, inland waterway or short sea shipping (short sea).