In this paper a new type of GIS system for maritime navigation safety is proposed. The system takes advantage of the properties of the kinetic Voronoi diagram (VD), and uses the "quad-edge" data structure for the maintenance of the spatial relationships of ships and other navigational objects. The locations of ships are updated in real-time using a standard onboard transponder, and moving-points VD algorithms. These spatial relationships are used for collision detection and avoidance. The system is aimed at tackling the main cause of marine accidents - human errors - by providing navigational aid and decision support to mariners. A brief introduction into static and kinematic Voronoi methods is given and is followed by a discussion of different types of GIS systems for marine purposes. The state-of-the-art in maritime safety and its major developments are also covered.