Principals play an important role in creating positive school climates. However, principals are also at higher risk of having mental health problems and diminished wellbeing due to the complex nature of their work. Research has found that excessive workloads further undermine principal physical and mental health, with supportive networks and peer-supervision serving as examples of interventions found to improve principal wellbeing. Despite the limited research on supervision, its potential benefits are noteworthy, hence this study shares the impact of a peer clinical supervision (PCS) trial on Australian principals' occupational health and wellbeing. We analyse data drawn from focus groups with school leaders as participants to highlight that principals face significant challenges in their roles, and PCS, when designed and delivered in specific ways, can lead to positive outcomes. The findings offer new and innovative ways to build the knowledge and skills of school leaders that can help them navigate the complexities of their work, as well as support their own health and wellbeing.