The problem of introducing any system of routing at sea is how to achieve effective control at an international level without drawing up hard and fast rules or imposing restrictions that might well, in view of the impossibility of policing vast ocean areas, prove nugatory. We hold that it is better to replace the rigidity of the prescribed route (the only relevant example, and that inconclusive, is the North Atlantic Track Agreement) by the much more fluid notion of the ‘recommended and protected route’, for which we have adopted the name ‘naviroutes’.