This policy brief summarizes research results and provides guidance regarding decisions associated with school accountability. Unlike previous notions of accountability, a standards-based system examines outputs, such as student performance and graduation rates, as well as inputs like the amount of instructional time or the number of books in the school library. Most states have accomplished the work of adopting statewide content standards and are now engaged in developing assessments that measure what students know and can do in relation to the standards. Student testing is one component of an accountability system; another is rating school performance through methods that incorporate data from assessments and other measures of student success. Once school performance has been measured and rated, issues involving reporting the results surface. After school performance has been measured and rated, it is also essential that struggling schools and districts receive the help they need before they become subject to consequences defined by the accountability system, such as state- or district-imposed sanctions. The granting of rewards or the imposition of sanctions must rest on multiple indicators of school performance. Creating consequences puts teeth into accountability systems, but there is a lack of agreement among experts about their effectiveness and how they should be used. (Contains 15 references.) (SLD)