As an island state, Japan’s economic activities depend on maritime transport. One of the most important shipping routes is through the Straits of Malacca and Singapore. A half-century has now passed since Japan began undertaking activities for safety of navigation in the Strait. As sovereignty over this ocean space resides in the coastal States and bad feelings can linger between States over territorial issues, it is unprecedented for an outside country to become so deeply involved in the area over such a long period of time. National bodies, courts, and treaty organizations need to interpret and apply the Convention on the Law of the Sea in a comprehensive and forward-looking fashion.