part for their contribution to students' standardized test scores. The EPI series on Alternative Teacher Compensation Systems is aimed at informing the different stakeholders in education -- policy makers, school officials, teachers, parents, and the general public -- of the nature and consequences of instituting pay-for-performance in education. The series brings together experts from education and the social sciences to analyze key aspects of these policies. The first report in this series (Adams, Heywood, and Rothstein 2009), published earlier this year, looked at the use of performance-based compensation and evaluation outside of education. In that report, economists Scott Adams and John Heywood argued that performance-based pay tied to narrow measures of job performance are not nearly as ubiquitous as common wisdom suggests. Formulaic rewards based on narrow quantitative indicators -- like the ones often proposed by education reformers -- are important in only a small fraction of professional occupations and are concentrated in real estate, sales, and especially the financial sector (which in retrospect has not worked out so well). Richard Rothstein highlighted pervasive evidence of distortions and gaming behaviors in other sectors of the economy, both public and private, that have relied on strict quantity indicators for pay-for-performance to improve outcomes. Rothstein concluded that such problems are particularly severe in sectors like education, where output is difficult to measure and collaboration is essential. This volume -- the second in our series -- consists of two studies by Susan Moore Johnson and John Papay, both of the Harvard Graduate School