For much of the last two decades, the narrowed focus on raising test scores under No Child Left Behind left important aspects of education untended. Since 2016, when the Every Student Succeeds Act (ESSA) enabled a more comprehensive look at accountability, state leaders have heard growing demands for a whole-child approach that emphasizes students' social and emotional well-being along with a broader approach to academic development. ESSA renewed attention on the learning environment itself, which plays a critical role in children's ability to learn and thrive. A positive school climate--where students feel a sense of safety and belonging and where relational trust prevails--improves academic achievement, test scores, grades, and engagement and helps reduce the negative effects of poverty on academic achievement. To bring about such environments, teachers, paraprofessionals, and school and district leaders must be prepared to create the school and classroom structures that encourage secure relationships. Preservice preparation programs and professional development should cultivate knowledge, skills, and beliefs that build educators' understanding of student needs and their ability to support learning and development. This article discusses principles for practice to help create a positive school climate. The authors explain the importance of preparing educators to gain the knowledge, skills, and attitudes to meet their students' needs. Considerations for policymakers are included.