The operation of ships has the potential for polluting the marine environment. The potential is reduced if there are adequate facilities on board to manage waste effectively and adequate and convenient facilities ashore to receive the waste when the ship reaches port. Such waste management systems will only be implemented if suitable regulation and control measures exist.

The MARPOL 73/78 regulations implement the International Convention for the Prevention of Pollution from Ships, and define measures to protect the marine environment from operational pollution. A series of annexes (I - V) cover pollution by oil, noxious liquids, harmful substances in packaged form, sewage and garbage. Annex VI, which has been adopted recently but not yet entered into force, aims at extending the regulations to cover air pollution from ships. These regulations have been developed over a number of years and are in place, but there is significant concern over their real workability.