# Theoretical Framework (Module) for Short-Sea Shipping System Evaluation
## 1 Introduction  
Short-sea shipping, abbreviated as SSS, is the maritime transport of goods over relatively short distances, as opposed to intercontinental cross-ocean deep-sea shipping. In the context of European Union (EU) transport statistics, it is defined as the maritime transport of goods between ports in the EU (sometimes also including candidate countries and EFTA countries), on one hand, and between ports situated in geographical Europe, on the Mediterranean, and on the Black Sea, on the other hand [1, 2]. The development of short-sea shipping affects the functioning of supply chains. Therefore, SSS and logistics operators should carefully analyze the conditions of their operationsand their place in these chains, as well as properly organize transportation and service provision processes, taking into account possible disruptions [3; 4; 5]. Ports play an important role in supply chains. A wide range of specific services are provided through an SSS system. Services can be provided by a single SSS company or by several transport companies on a commercial basis, but in some cases, a single SSS operator can manage the entire process. In addition, the SSS system should have vessels and equipment required to provide specific services [3; 4; 5]. Short-sea shipping (SSS) is oriented towards shipping between EU ports and is mainly concerned with legal issues such as decreasing the number of documents and procedures. Nowadays, there are many ports and fixed shipping lines between ports operating in various countries that offer transport services to customers. SSS is one of the transportation systems that allows one to optimize transportation processes between ports. In addition, the SSS system can offer other additional services such as cargo handling services, optimization of vehicle utilization and storage space, etc. [4; 5]. In some countries, there are limitations to creating SSS lines, but those countries possess many small and medium-sized ports located in different places, and it is difficult or even impossible to integrate them physically. The relevance and novelty of the article is an attempt to theoretically substantiate and practically verify the possibility of combining the logistics functions of port located in different places by creating SSS, in which representatives of small and medium-sized ports \"scattered\" in specific regions would participate in joint activities to minimize transportation costs and provide better services to clients. The SSS concept is intended for ports, shipping companies, and other transport service providers to make sustainable decisions regarding optimal cargo transportation between ports and other locations where maritime transport is or may be involved in transport processes [4; 5; 6]. It should be noted that large companies have more opportunities related to the organization of cargo transportation using SSS, including the optimization of transport processes using SSS and other types of transport, for example, rail or road transport. In the case of the need to transport relatively small cargo lots, the SSS system is important, since the combination of small consignments of goods with other consignees' assignments allows for the optimization of transportation processes [3; 5]. The aim of the article is to theoretically substantiate the possibilities of developing a short-sea shipping (SSS) system by combining the activities of existing and developing inter-port shipping lines and terminals into a single entity in order to reduce the cost of transportation services and the delivery time of goods, as well as to create a comprehensive range of transportation services needed by customers. Modern supply chains operate using an SSS system that includes shipping lines, intermodal terminals located in seaports and other locations, and the linear infrastructure of maritime transport. This infrastructure can be dispersed, so it is difficult to directly (mechanically) organize SSS processes.