This report reviews the findings of an ecological/economic analyses regarding the on-going and prospective efforts to reduce eutrophication of the Baltic Sea, conducted by BalticSTERN, an international research network.

The results indicate that the overall benefits of fulfilling the targets of the HELCOM Baltic Sea Action Plan (BSAP) clearly outweigh their aggregate costs, suggesting that the BSAP is an economically sound plan for solving the transboundary eutrophication problem. The cost of inaction - not implementing the objectives of the BSAP - would be significant.