Despite calls for research-based policies, other types of evidence also influence education policy, including personal experience, professional expertise, and normative values. This article focuses on the Common Core State Standards (CCSS) initiative, examining how research use varied over stages of the process and how it was integrated with other types of evidence. By drawing on elite interviews, we find that CCSS promoters and developers used evidence in much the way that policy analysis research would predict and that while research evidence was a major resource, it was combined with other types of evidence depending on political and policy goals at different stages of the CCSS process.