In an era of fierce debate over the relevance of facts and expertise in Washington, it is noteworthy—and curious—that evidence-based policymaking appears to be having a bipartisan moment. Consider a few examples from Congress: the Every Student Succeeds Act of 2015, with its emphasis on evidence; the Evidence-Based Policymaking Commission Act of 2016; and the pending Foundations for Evidence-Based Policymaking Act of 2017. For its part, the Obama Administration entrenched evidence-based policymaking as a key priority throughout the budget process, and the Trump Administration has continued to encourage that work. Both Republicans and Democrats in Congress and the White House seem enthralled with the promise of evidence-based policymaking. ...