In migration research there is an ongoing, growing debate about the limited impact of academic research on migration policy making, accompanied by a plea for more scientifically informed, evidencebased migration policy. These debates, however, rarely empirically engage with the question of how policy actors inform themselves and make judgements about international migration. In light of this gap, the presentation discusses processes of knowledge production in migration governance, by focusing on the sources policy actors rely on to form their insights about immigration. The presentation underlines that the migration policy field is an arena in which policy actors have to cope with political pressure, uncertainty, and ambiguity. Judgements about international migration inevitably rely on past experiences, new information in turn is filtered by relationships of trust regarding the sources, as well as by pre-set organizational goals and logics. Based on these empirical insights, the presentation eventually concludes that claims for more academic evidence-based policymaking are based upon a simplified understanding of what policymaking and the formation of knowledge claims about immigration are about, as well as the role of migration research.