Convention

A convention is a binding multilateral treaty adopted under IMO auspices that, once in force, obligates the states party to it. Major IMO conventions include SOLAS 1974, MARPOL 73/78, STCW 1978, COLREGs 1972, and the Load Lines Convention 1966. The IMO develops and adopts conventions but does not enforce them; flag, port, and coastal states implement them in national law. Each sets its own entry-into-force threshold, usually a combined number of ratifying states and percentage of world gross tonnage. Technical detail is then updated by amendment, often under tacit acceptance.