Background: The COVID-19 pandemic shuttered schools across the United States, upending traditional approaches to education and requiring large scale school transformation on a pace never before seen. Though prior research on organizational change has emphasized the importance of working conditions for teacher satisfaction and student achievement (e.g., Johnson, 1990; Johnson & Birkeland, 2003; Bryk et al., 2010; Grissom & Loeb, 2011; Johnson et al., 2012; Reinhorn et al., 2017)., much of the coverage of schooling during the pandemic has focused on reopening decisions, rather than the remote environments in which most teachers and students engaged. Research Questions (RQ): (1) RQ1: What challenges did the pandemic and sudden change to emergency remote teaching present for teachers, and how did these challenges differ across teacher and school characteristics?; (2) RQ2: How did the pandemic and transition to emergency remote teaching affect teachers' sense of success?; and (3) RQ3: What role did working conditions play in sustaining teachers' sense of success during the transition to emergency remote teaching? Setting and Population: In total, our sample includes 7,841 teachers in 206 schools across 10 districts and 5 charter school networks located in nine geographically-diverse states (GA, IL, LA, MI, NY, SC, TX, VA, VT). Data are derived from the Upbeat "Teacher Engagement" surveys (fall and spring, 2020) and "Teaching from Home" addendum in the spring of 2020 (response rate: 81%). Upbeat is a fee-for-service education technology firm that supports districts and schools with teacher retention by conducting and analyzing surveys about teachers' working conditions each fall and spring (see www.teachupbeat.com for additional information). Practice: We examine teacher working conditions with surveys capturing teachers' perceptions about five broad dimensions of their working conditions: collaboration, communication, professional development, professional expectations, and recognition. We examine teacher working conditions at three points in time: the fall, the early spring in person (retrospectively), and the spring during remote learning. For each of these time periods, we construct two complementary measures: (1) teachers' individual perceptions about their working conditions, and (2) the average perceptions of their peers in the same school. Research Design, Data Collection and Analysis: Data for this study were obtained from two survey waves from the fall and spring of the 2019-2020 school year. Across the two survey waves, we captured teachers' perceptions about their sense of success and working conditions for three distinct periods during the 2019-20 school year (see above). We construct composite working conditions measures by conducting a principal component analysis (PCA) separately for teachers' responses in each of the three periods. We use ten items to construct the fall measure and the spring retrospective measure of working conditions and seven items for the spring measure during remote learning. We begin with a range of rich descriptive analyses (RQ1). Our primary empirical approach uses multilevel ordered logistic models within an event study framework to examine changes in teacher sense of success over the three time periods in a teacher-period panel dataset (RQ2). We then explore the role that teachers' working conditions during the pandemic played in moderating changes in their sense of success by allowing the remote teaching estimate to vary depending on working conditions (RQ3). Findings: Our findings suggest that the sudden move to remote teaching created substantial challenges for teachers' work and limited the degree to which students could engage in learning. We find that teachers at every career phase struggled with the shift to remote teaching, but often in different ways. In addition, we provide further evidence that remote instruction exacerbated existing inequities by disproportionately limiting learning opportunities for students in low-income and Black communities. Not surprisingly, 53% of teachers experienced a drop in their self-reported sense of success during the pandemic. Simultaneously, schools' efforts to support teachers appeared to matter. Schools with more supportive working conditions were much more successful at helping their teachers maintain a sense of success during the pandemic. Conclusions: We make several important contributions to research, policy, and practice. For one, our large and diverse sample of teachers across the country allows us to comprehensively describe teacher perspectives during remote learning. We also inform future research by showing that school environments are shaped by a dynamic set of organizational practices that can change over the academic year and are experienced in different ways by teachers in the same school. Finally, our analyses illuminate the importance of working conditions as key moderators of organizational and instructional change.