This study explored the nature and effects of leadership for learning in the context of Hong Kong primary schools. Employing a mediated model of leadership for learning, the study examined how school leadership practices are perceived and shaped in the high accountability context of Hong Kong school education. Consistent with other recent empirical studies of school leadership effects, the research explored the relationship between school leadership, school-level capacity for improvement and student learning outcomes. Regression analyses found a negative impact of principal leadership practices related to strategic direction and policy environments, but a positive impact of staff management and resource management practices in terms of enhancing support for students. Contrary to expectations, schools’ capacity in supporting students had less impact on student academic outcomes than the negative impact of resources capacity and workload of teachers. Instead, mixed impact was found between principal leadership and student academic outcomes; it was negative regarding practices in strategic direction and policy environment, but positive in leader and teacher growth and development. The study refines our understanding of how the socio-cultural and organisational contexts of schools shape successful school leadership.[Copyright © 2015 Philip Hallinger and James Ko.]