The main content of the report of the Responses Working Group—Ecosystems and Human WellingBeing: Policy Responses, was briefly introduced in this paper. Human use of all ecosystem services is growing rapidly. However, approximately 60% of the ecosystem services evaluated in the MA are being degraded or used unsustainably. Moreover, the degradation of ecosystem services could grow significantly worse during the first half of this century and is a barrier to achieving the Millennium Development Goals. The challenge of reversing the degradation of ecosystems while meeting increasing demands for their services can be partially met under some scenarios that the MA has considered, but these involve significant changes in policies, institutions, and practices that are not currently under way. This report examined the strengths and weaknesses of various past and current responses options that have been used to manage ecosystems; indicated the barriers that must be addressed to ensure the sustainable management of ecosystems; identified a number of promising interventions, including institutions and governance, economics and incentives, social and behavioral responses, technological responses, and knowledge and cognitive responses; and emphasized some elements of decisionmaking processes for sustainable management of ecosystems sustainably as well as some useful tools that can assist decisionmaking concerning ecosystems.