While land-based industry has been subject to strenuous emissions regulations over the past decades, air emissions from sea-going ships’ machinery has so far been largely unregulated. As a result, according to EU statistics, ships have become the single biggest source of sulphur dioxide (SO2) within the EU. The US EPA (US Environmental Protection Agency) reports similar findings, i.e., that the proportion of air pollutants released which can be attributed to the shipping industry is increasing. MARPOL Annex VI aims to reduce emissions from ships through international regulations, which hopefully will discourage states from enacting unilateral regulations problematic to the shipping industry.