This paper first, introduces the concept of mainstreaming ecosystem services by showing its relevance for development planning. Second, it presents the role and importance of strategic environmental assessment in designing and implementation of development policy. Third, the paper sets-out the concept of economic valuation of ecosystem services by discussing what it means and what is at stake if valuation of ecosystem services is ignored in the process of development policy making. The methods of capturing economic contribution of ecosystem services at policy level are discussed with examples in the paper.

The main focus of this paper is how ecosystem services can be used in policy scale environmental impact assessment. The paper argues that ecosystem services can be an appropriate indicator to weight developmental policies, programs and plans to ensure the consideration of environmental balancing at the policy level. The paper suggests that the roles of ecosystem services in macroeconomic policies including ecosystem accounting, poverty alleviation and employment generation can be used to link environmental policies and SEA with development policies for a successful impact assessment at policy and program levels. By building upon the various contemporary initiatives within UNEP and outside, the paper in its synthesis section, flags-up necessary knowledge gaps, challenges and lessons learned in integrating values of ecosystem services in strategic environmental assessments.