One of the causes of ships’ accidents are errors in the communication between navigators in charge of ships concerned. The most common causes include a lack of communication, misunderstanding of a received message, incorrect choice of the type of message or misinterpretation of the information exchanged. These errors can be significantly reduced by the automation of intership communication processes, in particular by a developed automatic maritime communication system. The decision to communicate is as essential as communication itself. This paper presents the problem of identifying situations requiring the establishing of communication by a sea-going vessel. A definition of the need to establish communication between the vessels is associated with the acquisition of data, analysis and evaluation of the navigational situation and the relevant inference process. Based on an analysis of the process of identifying navigation situations which require communication between proceeding ships, the model of automatic identification of such situations has been develope