This report is the fourth in a series examining the magnitude of the teacher shortage and the working conditions and other factors that contribute to the shortage. The series finds that the teacher shortage is real, large and growing. When indicators of teacher quality (certification, relevant training, experience, etc.) are taken into account, the shortage is even more acute than currently estimated, with high-poverty schools suffering the most from the shortage of credentialed teachers. Like the other reports in this series, this report explores a probable factor behind the exodus of teachers from the profession and the shrinking supply of future teachers: the working environment for teachers, broadly referred to here as the "school climate. The report shows that school climate affects teacher satisfaction, morale, and expectations about staying in the profession. It also shows that school climate is challenging for a number of reasons: Teachers confront widespread barriers to teaching and learning, face threats to their emotional and physical safety, lack influence over school policy and what and how they teach in their classrooms, and suffer from dissatisfaction and low motivation. The report further demonstrates that there is a significant relationship between these indicators of difficult working conditions and teachers leaving the profession. And finally, as in previous reports, the authors provide evidence that working conditions are more challenging in high-poverty schools than in low-poverty schools, which compounds the problems already identified in this series.