In dealing with wicked problems, policymakers increasingly are confronted with three competing
‘knowledge claims’: the notion of evidence-based policy, alternative ‘commons knowledge’ created
by citizens, and ‘fact-free’ politics. Consequently, the knowledge base for dealing with wicked
problems is becoming increasingly contested. This paper analyses the ways in which these three
competing knowledge claims interact, and the consequences of their interaction, through a case
study of the dynamics of knowledge claims in Dutch climate policy. The paper concludes that the
quest for evidence-based policy may constitute an impediment to progress in finding common
ground in practical policies
