Social and emotional competencies and skills help students succeed in school. In fact, researchers have documented significant academic gains for students who participate in social and emotional learning programs in which they can strengthen their social and emotional skills (Durlak, Weissberg, Dymnicki, Taylor, & Schellinger, 2011). Skills such as growth mindset (Blackwell, Trzesniewski, & Dweck, 2007), sense of belonging (Allen, Kern, & Vella-Broderick, 2016a; Allen, Vella-Broderick, & Walters, 2016b), and grit (Duckworth & Quinn, 2009) have been shown to correlate to student grades, scores on achievement tests, attendance and other academic outcomes. Given the influence that social and emotional skills have on student academic outcomes, some policymakers are considering using measures of these skills to assess the performance of teachers and schools. In some states and localities, student perceptions of their social and emotional development are being considered for high-stakes accountability purposes, with incentives and consequences for schools based upon scores on these measures. This paper uses both a systematic review of research on these competencies and skills as well as focus groups with National Network of State Teachers of the Year (NNSTOY) teachers to examine whether measures of social and emotional learning are appropriate for use in accountability systems. Specifically, the authors consider the following topics: (1) the role of teachers and schools in fostering social and emotional competencies and skills; (2) the use of data about social and emotional competencies and skills; and (3) perceptions about the appropriate use of measures of social and emotional development in accountability systems. For the first two questions, they examined the academic studies that have addressed it, and then discussed the questions with teachers in focus groups. For the third question, they described policies for including these measures in accountability systems and researcher opinions about doing so, and then discussed the question with teachers in a focus group.