Background/Context: This article describes the fundamental role of social justice in public education and professional teacher education. Purpose: The purpose of this policy analysis is to explicate the theorizing, conceptualization, formalization, and implementation of the first standard for social justice teaching and teacher education in U.S. history, published by the National Council of Teachers of English and approved by the National Council for the Accreditation of Teacher Education in November 2012. Design: Using a policy narrative approach, the authors explicate the grassroots political processes, professional political action and advocacy, and policy procedures and scholarship undertaken to construct a successfully vetted, approved, and fully implemented national policy in one subject-area professional association (SPA). The authors demonstrate how other SPAs and affiliated groups may pursue similar policies for socially just teaching and teacher education across disciplines, fields, and contexts across education. Conclusions: Using research to theorize responsive teaching pedagogies and using findings from social psychology research to generate a socially just orientation to teaching in public schools, the authors highlight the ways in which social justice teaching is not simply a possible orientation for professional educators to consider but a fundamental tenet and primary consideration of public education overall. The authors conclude that SPAs and public education professionals not only may but must engage in social justice policymaking for educational equity in order to succeed in attaining education reforms that truly serve the public good.