The importance of the principal's role in improving student learning outcomes has been acknowledged, however, there is global concern about the availability of appropriate professional learning for principals. This article explores the impact on host principals of a shadowing and mentoring intervention designed to prepare New Zealand aspiring principals for secondary school principalship. It discusses the findings from the qualitative evaluative study that aligns with constructivist paradigm and suggest that the intervention was a vehicle for professional learning for the experienced principals who were shadowed and who mentored the aspiring principals. The nine host principals who were interviewed believed that the intervention was a reciprocal one that reduced their isolation; stimulated critical reflection on their leadership actions; encouraged them to view their school culture through a new lens and improved connectivity between schools. As such it provided access to highly relevant professional development in their own context through dialogue with a professional colleague. It is recommended that shadowing and mentoring be considered an effective approach to meet the needs of experienced principals.