Mandate of the IMO
The International Maritime Organization (IMO) is a specialised agency of the Organisation of the United Nations (UN) and has been established in 1948 by the Geneva Convention on the International Maritime Organization and met for the first time in 1959. Its mandate includes the protection of the marine environment against shipping activity.
The purposes of the IMO include the provision:
– of ‘machinery for cooperation among Governments in the field of governmental regulation and practices relating to technical matters of all kinds affecting shipping engaged in international trade; to encourage and facilitate the general adoption of the highest practical standards in matters concerning (…) [the] prevention and control of marine pollution from ships’; and
– ‘for the consideration by [the IMO] of any matters concerning shipping and the effect of shipping on the marine environment that may be referred to it by any organ or specialized agency of the United Nations‘.
To this end, the IMO has the function to ‘provide for the drafting of conventions, agreements, or other suitable instruments’.
The IMO has 175 Member States, 3 Associate Members and 151 Observers (66 Intergovernmental Organizations and 85 NGOs – ACOPS was one of the first environmental NGOs to become an observer). Only Member States can vote.
Role of the IMO in the protection of the marine environment as a competent international organisation under the Law of the Sea
Critically, the IMO is also the competent international organisation for shipping activities under the United Nations Convention on the Law of the Sea (the LOSC or UNCLOS), including for the establishment of international rules and standards to prevent, reduce and control pollution of the marine environment from shipping activities. Under the LOSC, globally accepted rules and standards established by the IMO are minimum standards to be regulated on globally by all states (importantly, flag states and coastal states).
This flows from the fact that (1) most of the 174 Member States of the IMO are a party the LOSC; and (2) for those states that are not a party to the LOSC, these provisions of the LOSC are now generally considered to have become part of customary international law, meaning that these provisions form part of the body of international law and are binding on all states. This also means, that rules and standards adopted by the IMO become applicable to all states, even to those states that may have not elected to become a party, from the moment that these rules and standards can be considered to have been globally accepted. There is a strong argument that from the moment that an IMO treaty comes into force (which generally requires that more than half of the commercial shipping fleet has become a party), this treaty sets generally accepted rule or standard for the subject it deals with.
Institutional Structure of the IMO
The IMO has 8 main organs, composed of an Assembly of all the Members, a Council of Members elected by the Assembly, a Secretariat and 5 specialised committees and their subsidiary organs. The Marine Environment Protection Committee is one of these 5 committees.

For further details of the workings of the IMO, see the useful IMO guide prepared by the Centre for International Law at the National University of Singapore.





