International shipping is responsible for a significant share of air pollutant emissions, especially regarding SO2. In order to limit air pollution’s negative impact for human health and the environment, Northern America and the European Union established sulphur emission control areas (SECA), under cooperation with IMO. Since 1 January 2015, the maximum sulphur content of marine fuels used in SECAs is reduced from 1.0% to 0.1%. Before and during its implementation, the reduction of the SECA fuel sulphur content led to discussions about the availability of low sulphur fuels and price effects. Also its impact on the industry, like company or service shut downs, potential shifts towards road transport as well as the need for effective surveillance schemes for compliance and enforcement were subject to discussion. The objective of this study is to present an ex-post assessment showing the first experiences under the 0.1% fuel sulphur regime, focussing on air quality, socio economic benefits, impacts on business, and compliance and enforcement.