This issue of CPRE Policy Briefs summarizes the findings on issues related to teacher quality in the chapter authored by Thomas B. Corcoran in the book, "The State of Education Policy Research." The report also draws on discussions that took place during a 2006 policy briefing on teacher labor-market issues held in Chicago and sponsored by the Spencer Foundation. The backdrop for this review is a continuing debate over teacher quality. The "professionalism" viewpoint is that teaching is work that requires significant preparation and support and rigorous licensing standards, a view that holds all teachers should have the content knowledge, teaching skills, and cultural understanding to serve all students well. Supporters of professionalism expect a teacher to know curriculum, learning theory and assessment, to have technical skills, and to understand school and community cultures. The "deregulationist" view maintains that teaching is a task that most intelligent individuals can do, that the demands of teacher licensing are unnecessary and costly, that the skills required can be learned on the job, and that alternative routes into the profession can expand the pool of potential teachers. Six domains that affect the quality of teachers and teaching are discussed: (1) Licensing and Alternative Routes; (2) Teacher Education Policies; (3) Teacher Induction; (4) Professional Development; (5) Teacher Compensation and Evaluation; and (6) State Data Policy and Data Systems. The report concludes that answers are mixed regarding whether sufficient research evidence exists to guide policy development in these areas. Compelling evidence is available about the effects of induction, with a growing evidence base about the qualities of effective alternative route-programs. Lacking is compelling evidence about teacher licensing, teacher education, and teacher compensation reforms, although the evidence about some aspects of teacher education is useful. The development of statewide data systems linking student and teacher data should lead to studies that will fill in some of these gaps. However, based on current results, it is unclear whether policymakers presently or will in future use the results of these studies to guide their decisions. The report concludes that educators and educational researchers need to think harder about how and to whom research findings are disseminated. Noting that policy makers pay attention to public and institutional pressures for action, the author advocates for the policy research community to become more media-wise, and to learn from the social marketing efforts that affect public health, conservation, driving habits, and other areas of social behavior and social policy. (Contains 2 tables.)