The research reported in this special issue has been undertaken by members of a long-standing network of scholars from more than 20 countries, speaking several first languages and embedded in a range of policy and cultural contexts with different educational systems. They are members of the International Successful School Principalship Project (ISSPP). These scholars want to understand, for example, the nexus between the professional, the personal, organizational and the policy dimensions, the purposes, values and educational agendas that drive successful principalship; how they manage the influence of broader cultural and policy environments that have intensified teachers' work, increased workload and reduced teachers' professional autonomy; whether they acted similarly and differently in different social, regional and national contexts and how they achieved and sustained success over time.Their collaboratively designed, multiple-perspective, multi-layered case studies carried out in primary and secondary schools in a range of socioeconomic and geographic regions over a period of 24 years by members in 25 countries. Over that period, the research revealed that successful principals internationally share a common understanding, expression and application of broad educational purposes; strongly held values; competences and capabilities; that in achieving and sustaining success, they use combinations and accumulations of strategies and actions, and that these differ in their timing, timeliness and intensity. The research also revealed that the educational world of the principal is complex, uncertain and non-linear and that all things are connected in different ways. Its findings support the premise that, “any attempt to theorize correlations – either at a micro or macro level – eventually has to focus on the actions and interpretations of individual and groups, as it is only at that level and through such processes that connections are made/achieved” (Biesta et al., 2011, p. 230).Essentially, the ISSPP corpus of empirical research knowledge, the largest of its kind internationally, has developed a more nuanced, complex, practice-informed view of successful school principalship as agential and navigational work in shifting layers of different but interconnecting and interacting systems than is able to be contained, for example, within existing generalized adjectival “models”, leadership “styles”, self-reports, critical theories and literature which primarily focuses on measurable academic achievement as a means of positioning them as “effective.” Although these are helpful in their contributions to understanding the work of successful principals, the ISSPP research design and its explanatory power have enabled additional research-informed insights into the worlds of successful school principalship, which overcome the research of individuals represented in journal publications that are often the product of the endeavours of individual or groups of scholars seeking to understand and add knowledge to a particular field of knowledge. Less often, these are able to illustrate or represent knowledge through collaboratively agreed-upon research methods and are underpinned by a shared theoretical stance and so are unable to present a robust, comparative, methodologically sound perspective.As a result of extended reflection on the limitations of its largely empirical research, the ISSPP research adopted an underpinning conceptual framework that has been explicitly theorized within human ecological systems theory (Bronfenbrenner, 1979) and informed by complexity theory. Originally designed to study how multi-layered environmental layers affect in different ways a child's cognitive growth, Bronfenbrenner's (1979) recognition of multi-layered environmental “layers” in which we live is now being used in ISSPP members' research to understand and analyse the complexity of the work of successful principals as they too navigate these environments.Ecological human systems theory identifies schools as “complex adaptive systems” (Kershner and McQuillan, 2016; Preiser et al., 2018) in which the interrelated, often reciprocal nature of human and non-human (environments and resources) elements within and across schools, school systems and government combine to influence the whole (Day, 2016; Shaked et al., 2018). The schools of these successful leaders were found to be resilient and complex adaptive systems. Successful principals in the papers in this issue diagnosed patterns emerging from their navigation of five “layered” systems in the ecology of education, identifying and managing these complex environments by anticipating and identifying potential patterns within and across five layered environments: microsystems that constitute the direct interaction environment for principals (within-school contexts such as school location, level and student populations); mesosystems further from the centre that constitute a network where principals navigate and interact (e.g. district, municipality, parents and immediate communities around the school); exo-systems (e.g. indirect environments such as local or regional policies); macrosystems (e.g. national educational policy, social, political and cultural contexts of a country or region) and chronosystems (e.g. how principalship changes over time). These systems interact with each other but are also partially constituted of other interactions with larger systems of governance (Haggis, 2008), and each of these elements (teachers, school and educational and cultural) constitutes a system. Such human systems theory focuses on understanding schools as particular systems that need to be understood locally, contextually and holistically (Sun et al., 2024).This conceptualization is not imposed upon but empirically “fits” the research purposes, design and findings of the ISSPP research, enabling the creation of a more detailed, authentic picture of the personhood, professionalism, relationships and actions of principals in the context of their work. The researchers find, in ways that single-lens snapshots and accounts by individual researchers using single-lens paradigms and single-lens methodological approaches cannot, that principals, nested inside interacting complex systems within the ecological environment, are understood as being not only part of a profession but also part of a school organization that is one small piece of a whole educational system, and this system, in turn, is part of a local, regional and country's historical and present cultural and political heritage (Sun et al., 2024).The framework's emphasis on the dimension of time especially enables an exploration of leadership practices over different non-linear phases. This temporal aspect reveals a limitation of the design of many established leadership frameworks, which often overlook how practices evolve over time. Applying Bronfenbrenner's human ecological systems to principalship not only continues the ISSPP's long-standing research over a 24-year period in bringing context out of the shadows but also illuminates the dynamic interaction between principal agency and ecological systems over time. It helps make sense of the layered networks and reciprocal influences among school stakeholders, as well as the complex interplay of multiple coexisting ecological factors – educational, political, cultural and historical – on principal leadership.The first article, “Working together towards school success in a rural school context: ‘It works well but we are not satisfied’”, Grimm et al. (2026) illustrates how one successful principal navigates the interplay between the national macrosystem layer, e.g. national curricula and reforms, equity and quality assurance processes, external evaluations and inspections) and the exo-system local education authorities (school district) layer, which has considerable autonomy in implementing and adapting national policies to local conditions. The case school is a rural public school in northern Sweden, with approximately 430 students from preschool to grade 9, 52 teachers and a small percentage of immigrant students located in a sparsely populated municipality characterized by stable employment and a cohesive community. The principal interprets and adjusts policy directives to fit the unique rural context while maintaining consistency with national standards. Situated within this complex interplay, relations and interactions with the superintendent and parents, as well as the culture, events and activities in the community, indirectly affect principals’ and teachers' work and decisions. By using Bronfenbrenner's layered environmental systems, the authors used the chronosystem and school history to understand how successful principals navigate, build and sustain structures and cultures to meet external policy, local context and school internal needs and expectations. The ecological system layers are interrelated and reciprocal. As the authors comment, “The mesosystem provided the foundations of what happened in the classroom” and “a great influence and interaction with all respondents in a way that builds understanding and mutual explanation in what is seen as successful in the local context”. While expectations from the macrosystem (national level) often prioritize individual students' academic results and innovation in teaching, striving for success in relation to broader moral and ethical educational purposes requires careful interpretation and active choices applied within and across international, national and local layers of system influence.The Scotland article, “Successful school leadership in Scotland: a journey to sustainable improvement”, Constantinides (2026) pays particular attention to a combination of the range of system factors influencing principals' leadership practices, situated within the nested layers of Bronfenbrenner's (1979) ecological framework. The study involves three urban and rural Scottish schools serving diverse populations in socioeconomically mixed areas, which face challenges related to economic deprivation and community integration. The three principals were guided by a work ethic and equity-based value system, built a collaborative improvement culture and coped with uncertainty by adapting their approaches to create responsive schools suited to local conditions. They skillfully navigated the Scottish education context, resulting from a series of educational reforms over the past few decades with a strong focus on equity, quality assurance and sustainable improvement (macrosystem). Yet, they aligned national education policies with local needs and community expectations.From a macrosystem perspective, government policies and reform initiatives require schools' capacities and practices to align with and accelerate student achievement. Principals in the study developed a rich understanding of macrosystem-level policies, complementing bottom-up, locally directed improvement initiatives to align standards, assessments and curriculum with both external policy demands and school needs. At the microsystem level, principals act as critical agents of change, making sense of policies, fostering collaboration and creating supportive structures to sustain a productive school ecology. This study highlights the importance of aligning with local priorities to ensure coherence across systems, even amid external tensions. Navigating contradictions or disputes can help integrate reform with regional needs.Findings also show that the notion of success has a broader meaning, encompassing not only academic achievement but also nurturing sustainable communities for the future. Additionally, the article discusses key dispositions that principals demonstrate, including responsibility, high standards and a commitment to the well-being of both students and staff, prioritizing the collective good over individual interests. They celebrate success, foster trust through meaningful communication and build a collaborative culture grounded in empathy and shared values. The study provides important insights into how successful leadership practices and dispositions both shape and are shaped by a complex interplay between elements and agents within the educational ecology. As the authors commented, “Improving the quality of education for all as well as teachers' active engagement in effective learning was difficult work but appreciated and supported people's efforts amidst periods of uncertainty that stemmed from different layers of the ecology (e.g. school context-specific mesosystem and more broadly situated in cultural, socioeconomic and political conditions-macrosystem).”The Australian article, “Context, leadership and school success: Australian suburban, rural and remote cases from the ISSPP”, Gurr et al. (2026) focuses on schools serving diverse populations, including culturally diverse students, Indigenous communities (exo-system layer) and students from low socioeconomic backgrounds. Principals operate within the Australian education context, which involves a combination of centralized policies and local autonomy (macrosystem), navigating national accountability requirements while fostering local adaptation and community engagement.The authors use an “open systems” model to illustrate how schools operate in ways that frame leadership as a continuous cycle of input, transformation and output, with feedback loops that inform each stage, integrating contextual complexities with leadership practices. The model views schools as complex entities within several wider contexts. The three cases show that the type of school and school system, as well as the school's community (students, families and staff) and location, influence how principals lead their schools. The open systems model of successful school leadership described in this Australian study interconnects with Bronfenbrenner's ecological systems theory by conceptualizing schools as complex adaptive systems influenced by the multiple layers of context represented in Bronfenbrenner's theorization.The fifth article, “A case study of successful leadership by an elementary school principal in Japan”, Yada et al. (2026) features a successful principal of an urban public primary school in Japan with approximately 400 students. The school serves a relatively stable, socioeconomically mixed community, characterized by strong local ties and cooperation. The principal navigates the intricate contexts of Japan's centralized, hierarchical educational system managed by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), emphasizing educational equity and quality at the macrosystem layer and municipal boards of education that influence school practices at the exo-system layer. At the mesosystem level, schools face challenges related to teacher workload, age imbalances among staff and curriculum overload. The principal addresses these challenges by promoting inquiry-based learning, identifying issues efficiently and making data-led decisions timely to achieve short improvement cycles, fostering a collaborative and adaptive school environment and balancing top-down leadership for sharing his vision and promoting research activities with bottom-up leadership that enables teacher autonomy and professional development. He also demonstrates strong agency by actively shaping the school's direction through vision statements, data analysis and teacher collaboration and professional development.Almost all the articles in this special issue on leading, managing and sustaining success position school principals as carrying out their work in interacting multi-layered systems, which they must navigate on a daily basis and over time. Readers will note that the orientations of the papers do not always strictly conform with, for example, Bronfenbrenner's theorization or “open systems” theory. However, the findings in all demonstrate clearly that these successful principals hold similar values and purposes for the education of their students and that their strategic approaches vary by context and are adapted over time in response to their contextually sensitive judgements of the potential individual and combined impact of the advancing emergent and actual external (chronosystem, macrosystem and exosystem) influences and internal (microsystem and mesosystem) emergent challenges. The strategies successful principals employ are never singular, never formulaic, and always related to context and purposes. Success is often the result of time and context-sensitive combinations and accumulations, rarely achieved in a linear way, without pauses and unexpected interruptions, but always in accord with their commonly held broad humanistic and/or moral purposes. These successful principals make timely decisions, which are sensitive to circumstance, but are always value-driven as they strive to align actions with interactions within and across multiple layers of influence. What marks all their work within and across these systems is their agency, human caring, abiding hope for a better future for their pupils, capacity for resilience, and ability to draw upon a range of personal resources, creatively overcoming barriers and constraints, managing perturbations and uncertainties and ultimately prevailing in building and sustaining success across broad rather than narrow educational purposes.
Day et al. (Mon,) studied this question.