National governments use evidence selectively to argue that a successful policy intervention in one local area should be emulated in others ("evidence-based best practice"). However, the value of such evidence is always limited because there is: disagreement on the best way to gather evidence of policy success, uncertainty regarding the extent to which we can draw general conclusions from specific evidence, and local policymaker opposition to interventions not developed in local areas. How do governments respond to this dilemma? This article identifies the Scottish Government response: it supports three potentially contradictory ways to gather evidence and encourage emulation.