The final chapter of Part 1 provides an overview of national and international studies conducted in order to test the validity of recent theoretical models of Educational Effectiveness Research (EER). These empirical studies as well as relevant meta-analyses seem to provide support for the importance of specific factors included in the dynamic model of educational effectiveness and their measurement dimensions. Empirical studies also reveal relationships among factors operating at the classroom level, which help us to define specific stages of effective teaching. On the other hand, empirical studies have revealed possible ways to improve the dynamic model of educational effectiveness. In this chapter, we consider these possibilities and propose an improved version of the dynamic model, which is more parsimonious, especially since curvilinear relationships have not been identified and some factors and their dimensions have been found to be less important than expected in explaining variation in student learning outcomes. Suggestions about how to improve this model further, especially at the school level, are also provided, and an improved version of the dynamic model is proposed. This improved version also takes into account that schools should not only seek to improve student learning outcomes, but also aim to reduce differences in initial achievement of students from different socioeconomic backgrounds. In this way, the improved version of the dynamic model that is proposed 12 years after its initial development (i.e., the 2020 version of the dynamic model) may be able to promote not only quality, but also equity in education. In this context, the second part of this chapter aims to develop further the DA in order to explain in a more precise way the qualities that the Advisory and Research Team (A&R Team) needs in order to support teachers and schools in becoming more effective in terms of promoting both quality and equity in education. The conditions under which this approach can be used in order to have a significant impact on teachers’ professional development and on improving school effectiveness in terms of both quality and equity are also discussed.