To optimize the man-machine relationship different approaches are possible, the adaptation of man to the machine or of the machine to man. The first relates to training and selection, the second is generally called ‘human engineering’, now of great interest both in the naval and merchant marine context. Changing factors like the density of traffic in harbours, the harbour environment, the speed of ships and problems of manning and automation have all contributed to that interest. A ship designer is increasingly confronted with design problems where the man/machine relationship involves the operator as a controller. The desired increase in performance is achieved only if human possibilities are put to their best use.