This review of the English research strand of ISSPP highlights the pre-eminence of humanistic values in successful school principals’ work. It aims to answer the question: ‘How do the principalship’s moral purposes and contextual understanding shape the time-sensitive combinations of strategies that lead to sustained school success?’ It captures how success and ‘successful leadership’ are defined, applying complexity informed system theories from a multi-perspective viewpoint. The authors find that moral purpose and finely tuned contextual understandings, relationships, and actions are key to promoting improvement, including academic progress and student attainments. The evidence is that successful leaders go beyond a functional ‘human capital’ view of education. They discern the ‘right order’ in the multiple layering of strategies, actions, and relationships within and across internal and external systems of influence that overlap interact. They navigate these effectively, exercising both strong agency, resilience, values-led strategies and actions, optimism and hopefulness, with a focus on developing human capacity and capability development.