Even though the evidence-based movement and the concept of public good have been thoroughly discussed and from a range of perspectives in the literature, there is no general consensus on the definitions and nature of these terms and concepts. In this chapter, the author conceptualizes what is meant when educators speak of the concepts like "public good" and "scientific evidence" in order to develop an understanding of what the concepts imply and demand of us as researchers, policy makers and scholars in the field of education. The author also analyzes the studies on practitioners and policymakers' definition and use of evidence in educational policy and practice. Furthermore, the author provides nine guiding principles for educational researchers to generate scientific evidence that can promote a shared democratic vision of public good and recognize the plurality of goods and multiple principles of educational practice. At the end of the chapter, the author analyzes how the chapter contributors in this edited volume contribute to the literature on evidence and public good, and provides recommendations for the future studies. [For the complete volume, "Evidence and Public Good in Educational Policy, Research and Practice. Educational Governance Research. Volume 6," see ED613293.]