One of the key factors that contribute to effective management of schools is the professional development of principals. The role of the principal has become more complex with the dynamic and constant reforms in the educational environment. The present study focuses on the professional development of principals in New Zealand and Singapore. The identified categories for comparison include similarities in knowledge on leadership, models and skills that are important for aspiring principals. Differences include the selection process, programme design, modes of learning, futuristic projects and visits to other institutions. The study contributes to our understanding of key dynamics in the professional development of aspiring principals by identifying categories for comparison and discussing their relevance for analysing similarities and differences between these. The study also points to relevant interactions between professional development and the local environment.