Sustainability leadership requires vision for and commitment to a better world. It involves inspiring, guiding and motivating staff and students, creating opportunities for collaboration, and connecting diverse aspects of the school's activities so that the teaching, learning and practice of the school are joined up in their efforts to address sustainability. The key messages outlined in this report arose from discussions that took place on 8-9 December 2022 at the EU Working Group meeting on 'Supporting School Leadership for Sustainability'. Topics include: (1) challenges to sustainability leadership; (2) values and ethics; (3) distributed leadership; (4) professional development for school leaders; and (5) leadership entry points.