With the knowledge of possible outcomes, what kind of actions should we take? The Millennium Ecosystem Assessment scored more than 70 response options for ecosystem services, biodiversity, and drivers such as climate change and nutrient loading. This third volume in the Millennium Ecosystem Assessment series presents policy options, analyzing the track record of past policies and the potential of new ones. The challenge of reversing the degradation of ecosystems while meeting increasing demands for their services can be met only with significant policy and institutional changes. However, a difficult set of obstacles stand in the way of those changes. Policy-makers must keep in mind that there are both trade-offs and synergies between human well-being, ecosystems, and ecosystem services, and that decisions regarding these tradeoffs are difficult and often contentious. The Responses volume ultimately establishes policy options that have the greatest chance to overcome the obstacles and generate positive outcomes. It will serve as an invaluable guide to the creation of stronger policy frameworks for the future.