Abstract: This paper investigates how and why DHS data were used in select health policy decision-making processes and how best the use of evidence can be supported in future. We use data from in-depth interviews with 22 professionals working in health and policy think-tanks, government agencies, foundations, survey research, and non-government organizations. We undertake a cross-case thematic analysis of the interview content and available documents to develop three case studies (Malawi, India, and Rwanda) of evidence-based policymaking. These case studies outline the way in which DHS data were used in a variety of policymaking contexts and how it facilitated policymakers’ appreciation of the scope of problems, highlighted mismatch between population health needs and service provision, supported advocacy efforts, provided concise and compelling issue framing, and catalyzed high-level political commitments. The paper presents a framework that can be used to understand the use of evidence in health policy decision-making in developing countries. Keywords: Health policy, population health, survey data, developing countries