The document summarizes an evidence review on effective professional development. It reviewed 104 evaluations from 2002-2020. The review identified 14 mechanisms for effective professional development grouped into four categories: building knowledge, motivating teachers, developing techniques, and embedding practice into the classroom. It discusses how the design of the Early Career Framework and new NPQs for teachers address these mechanisms through goals, modeling techniques, feedback, and other measures. The document stresses that professional development is part of the larger process of implementation.