Moral distress is experienced when one knows the right thing to do, but cannot do it because of institutional or external constraints. This study aimed to understand the extent to which moral distress affects a school leader's role, and the key sources of moral distress. Using a web-based survey (n = 954) and focus groups including school leaders, we found that the increasing complexity of classrooms places competing demands upon school leaders. Moral distress emerged from expectations from school district leaders and parents. This study introduces moral distress to educational research, and provides a conceptual lens for describing the moral dimension of challenges that school leaders face. Future scholarship is necessary to understand the impact of moral distress on school leaders as they strive to adapt to increasing demands from both their districts and their school communities.