The paper introduces the results of research concerning modelling of ferry captain’s manoeuvres decision. The author’s probabilistic model has been validated with real time manoeuvres of the ferry m/f “Polonia” at the Ystad harbour by using Bayesian belief networks. Variables, quality factors, network example, model’s suggested settings of propellers and rudder for selected real manoeuvres have also been presented. Comparison to existing methods and models has also been presented. Finally, there are some conclusions concerning the described model. Are also included some proposed practical applications