There is a well-established literature identifying teachers as the most important school factor influencing student outcomes (Chetty, Friedman, & Rockoff, 2011; Rivkin, Hanushek, & Kain, 2005; Rockoff, 2004). While recent literature suggests that traditional measures of teacher quality such as credentials and additional degrees have little bearing on student performance (Boyd et al., 2009; Rockoff, Jacob, Kane, & Staiger, 2011), specific and consistent evidence about factors that do contribute positively to quality teaching have been harder to identify. In addition, the question of how to identify quality teachers presents a two-fold challenge: recognizing a successful teacher from the point of hire, and determining the qualities that contribute to student success in the classroom. In an effort to address these twin areas of concern and improve student achievement, the District of Columbia Public Schools (DCPS) has made efforts to both reduce uncertainty about teacher quality in its hiring system, as well as to more systematically identify, encourage and retain exceptional classroom teachers. By overhauling both the teacher hiring system as well as the teacher evaluation and compensation systems, DCPS has attempted to create better mechanisms and incentives for recruiting, retaining, and developing high quality teachers in its schools. Ultimately, DCPS expects these efforts will result in improved student achievement. This panel presents a series of papers that each address a different question about the results of the policy changes made in DCPS. Beginning with teacher selection, the first paper seeks to investigate how the collection of unique and rich data during the hiring process contributed to who was hired in the district, as well as whether those factors served to predict classroom performance in the early years of teaching. Turning to teacher performance, the second paper evaluates whether IMPACT, a newly structured evaluation system that provided substantive feedback to teachers, served to induce growth and learning among teachers, as well as which competencies teachers were and were not able to change in response to feedback and incentives. Uniting teacher quality with student achievement, the third paper assesses whether differential patterns of policy-induced teacher mobility within DCPS (e.g., voluntary attrition, forced separation) influence the patterns of student achievement within affected school-grade cells. Finally, focusing solely on student achievement, the fourth paper compares changes in test-based performance in DCPS before and after IMPACT to contemporaneous changes in DC charter schools, comparable schools in two urban Maryland districts, as well as districts participating in the National Assessment of Educational Progress Trial Urban District Assessment (NAEP TUDA). Together, these papers provide a comprehensive perspective on a seminal policy initiative that seeks to improve a major urban school district through focused and multi-dimensional efforts related to teacher effectiveness. Moreover, although all these papers are specific to DCPS, the reforms they study are a leading and much-watched example of similar policy initiatives currently being implemented in school districts throughout the United States.