The paper deals with utilization of evaluation results in policy-making and public administration. In the pursuit of this guiding question, the article is written in five steps. First, major variants of evaluation are presented with a particular eye to their respective utilization potential. Second, different concepts are sketched that have been forwarded to capture the utilization of (social) science-generated knowledge by political, administrative, and social actors. Third, looking at Germany, Switzerland and the European Union as cases in point pertinent research findings are discussed. Parts four and five contain summary, conclusions and some remarks on ensuing research needs. The political rationality and the underlying political will ...