Since 2010, a substantial number of large-scale, quantitative studies on preparation features associated with teaching effectiveness and retention have emerged. The purpose of this paper is to review this body of evidence and make sense of what it suggests for practitioners and policymakers. The paper begins by describing the groundbreaking work by the New York City (NYC) Teacher Pathways Project, which identified clinical experiences--including student teaching and pre-student teaching experiences--and its alignment with other aspects of programs generally, as predictive of teaching effectiveness. It then reviews literature on features of clinical experiences, including their duration, the features of the field placement schools in which they occur, and cooperating teacher characteristics. Finally, it focuses on coursework, beginning with new evidence on practice-based course simulations and then the amount of coursework generally. Within each section, the author summarizes research focused on teaching effectiveness measures followed by retention.