The objective of navigation is to ensure safe and economic operation of the craft and new trends and developments in navigation have to be judged against the return that they might be expected to bring in operating economics and reduction in accidents. Modern technology offers a wide range of fascinating possibilities, many of which will be discussed at this quadripartite meeting. The potential of these new trends and developments, however, cannot be judged just on the basis of the improvement they bring to the reckoning of position and course. This is but the starting point (Fig. 1) to a complex interaction between navigation, operator and the world at large. The operational navigation performance is determined by the interaction between the means of reckoning position and course, the operational situation and the human operator's interpretation of the operational situation in relation to such regulations, rules and procedures as have been established.