Rethinking boundaries to unite 11 fragmented schools: Systems Thinking as a meta-school in project management for assessing existential risks

Project management (PM) research has evolved through various schools of thought—from Optimization and Modelling to Governance, Practice and Sustainability. Existential risks such as climate-induced collapse, pandemics, and unchecked technologies exposes the limitations of these fragmented approaches. This paper proposes that systems thinking functions not as another school but as a unifying meta-school that synthesizes diverse PM paradigms to address existential risks—where cascading failures and cross-border implications demand a reconceptualization of project boundaries, governance structures, and stakeholder engagement. First, the paper traces the historical development of project management, highlighting development milestones when feedback models, soft systems methods, and system dynamics were introduced to develop insights from increasingly complex project activities. It then demonstrates how systems thinking complements existing schools by mapping interdependencies and emergent behaviours that traditional theoretical lenses may overlook. Finally, the paper outlines a research agenda calling for expanded methodological toolkits, interdisciplinary collaboration, and revised professional standards to address existential risks such as climate-induced collapse, pandemics, and unchecked technological growth. By adopting a systems perspective, project management can transition to proactive, transformative strategies that anticipate and mitigate existential-level disruptions to society’s long-term viability