Ex ante evaluation of legislation : an introduction / The context of the rise of ex ante evaluation / Ex ante evaluation of legislation torn among its rationales / The politics of the ex ante evaluation of legislation / Ex ante evaluation of legislation : between puzzling and powering / Pushing evaluation forward : institutionalization as a means to foster methodological growth of legislative ex ante evaluation / European impact assessment and the choice of alternative regulatory instruments / National experiences with general forms of ex ante evaluation of legislation : the cases of Germany and Sweden / Assessing the accuracy of ex ante evaluation through feedback research : a case study / Assessing corporate tax reform : incomplete information and conflicting interests