Early childhood classroom quality can be viewed from multiple perspectives—including parents, teachers, administrators, researchers, policymakers, and politicians. From the beginning of our work in the 1970s, we have defined and measured the quality of early learning environments with the Environment Rating Scales (ERS) from the perspective of the children in those environments. As quality definitions and measurement have changed through the decades since then, we have retained a focus on children’s perspectives and have continued to revise the ERS to better capture aspects of caregiver–child interactions and particularly language interactions as research has shown these to be particularly important for children’s development. We have maintained our view of the centrality of children’s needs across a wide range of developmental and personal health and safety domains so that teachers, directors, home-based providers, technical assistance personnel, policymakers, researchers, and others interested in high quality programming have tools to guide their work.