Abstract: Syftet med studien är att utforska och utvärdera möjligheten att, inom RoRo-närsjöfartsegmentet, kombinera SECA (Sulfur Emission Control Area)-anpassningsstrategier med slow steaming som energieffektivitetsåtgärd så att tjänstens konkurrenskraft jämfört med andra konkurrende trafikslag förbättras eller bibehålls. Abstract: The competitiveness of Swedish industry is marred by its geographical separation from mainland Europe and critical dependent on short sea RoRo shipping services for intra-European trade and passenger transport. The comparative advantage of goods and services produced by Swedish industry and enterprise are mitigated by limitations on its access to cost effective maritime transportation of sufficient capacity and quality. This issue is likely to be exacerbated with the enforcement of reduced maximum limit of the sulfur content of shipping fuel used in the Sulfur Emission Control Area (SECA) in the North and Baltic seas starting from 2015. The increased cost stemming from SECA compliance measures could potentially reduce the competiveness of short sea RoRo shipping thus resulting in so called modal back-shift. Paradoxically, reducing the negative external effect of the cleanest mode of the transport system would potentially lead to decreasing the system level environmental performance due to this effect. One strategy for coping with the simultaneous and contradicting requirements of reduction of external effect with reduced or at least sustained cost and quality of service could be the combination of compliance strategies with energy efficiency measures. Increasing the energy efficiency of shipping operations by way of reduction of sailing speed, or, slow steaming, is connected to negative abatement cost and thus, when combined with SECA compliance strategies, could potentially offset the additional cost of emission reduction at the same time as increased energy efficiency intrinsically enhances environmental performance. The service design, however, needs to be modified so as to accommodate the sustained service quality given the new, lower speed. The purpose of the study is to explore and evaluate the feasibility of combining different SECA compliance strategies with slow steaming as an energy efficiency measure in order to sustain or increase the competitiveness of RoRo short sea shipping as compared to competing modes. This includes considering the elasticity of the shippers’ demand with regards to service price and quality and providing an evaluation of the environmental performance of combining SECA compliance and energy efficiency measures.