In 2007 the Helcom (The Helsinki Comity), representing most of the countries around the Baltic, made an agreement for the future of the Baltic Sea, on reducing the nutrient input to the Baltic Sea and thereby avert further environmental damage, called the Baltic Sea Action Plan (BSAP). One of the results was nutrient reduction targets for each country - the BSAP targets. Because the Baltic Sea is such an international marine area, receiving pollutants from many countries, an international approach is necessary to make effective solutions. But is the BSAP the most cost-effective solution to the regulation of the Baltic Sea? And does the BSAP result in cost-effective reductions in the different countries, which is a requirement of the Water Framework Directive and the Marine Strategy Directive? These questions are studied and answered using a cost minimisation model for the Baltic sea, initially developed by Gren (2000) and, Schou et al 2006, now being under further development and extension within the Baltic Nest Institute in Roskilde. The model is a cost minimizing model for the reduction of nutrients to the Baltic comprising all countries around the Baltic sea. The purpose of this model is to establish a framework for prescribing cost minimising efficient scenarios of reduced nutrient loads to the Baltic Sea. Nutrient loads derive from both airborne and waterborne emissions. Three scenarios are presented and compared; one where the BSAP target is fulfilled by cost-minimisation, and one where the BSAP targets are set as target reductions for each countries. The comparison reveals what the additional costs of fulfilling a political target for each country are instead pursuing a cost effective solution for the Baltic Sea. In addition we simulate cost minimising solutions for obtaining the targets for each countries as compared with the BSAP plans. The paper contain a presentation of the BSAP, the cost minimisation model and the further development of this model upon the former versions, the cost minimising solutions to different targets in the Baltic, comparison of the two scenarios, discussion of these results compared with other analyses in the Baltic as well as a discussion of how to use these results with regards to the WFD and the Marine strategy directive.