In order to design and implement an impact strategy for an assessment process, it would be useful to provide examples that had a well-defined impact strategy, and to analyse the results of the strategy in terms of success and failure. Unfortunately, impact strategies in the area of global environmental assessment are hard to find. In 2001, the Social Learning Group found that self-conscious process evaluation was rare in the management of global environmental risks. It seems that evaluation and impact are treated, if at all, in an ad hoc manner. We do not yet fully understand these barriers, although concerns about time and resource constraints are often a factor, although good strategic planning and monitoring can address some of these concerns. Regardless, for the purposes of this Module, we chose to look at particular assessment processes that have had an impact, discuss the reasons for their success and provide pointers for the development of an impact strategy. Therefore, three case studies are explored below. The first is an example of a national level SoE report, from South Africa. The second and third involve major scientific assessments: the Intergovernmental Panel on Climate Change and the Millennium Ecosystem Assessment (MA). These assessments are considerably more detailed and academically rigorous than what is usually possible at the national level in an SoE or national IEA report. Nevertheless, both have deployed strategies to ensure that their findings impact international policy setting and decision making.