Based on a comparative analysis of three different evaluation traditions that have been developed during the last 20 years in Great Britain, the United States of America, and Scandinavia, it outlines the importance of a critical approach to the kind of evaluations that are commissioned and their underlying purpose(s). It also discusses the possible consequences of the current emphasis on strengthened evaluation of crime prevention. A brief history of the development of crime preventive evaluation is presented, followed by a comparative analysis of the three evaluation traditions' strengths and weaknesses. In particular Norwegian and Swedish governmental documents call for strengthened evaluations of crime preventive initiatives and development of operational measures that can form the basis for police management. This article argues that such contemporary evaluation initiatives may suffer due to a lack of critical approach to different evaluation traditions, and under the pressure of two rationalities that are not easily harmonized: scientific rationality and 'governmentality'. (Published Abstract)