Namuchana MaimbolwaMasaiti GiftMwelwa Kapambwe2026-03-272026-3-1110.47191/ijsshr/v9-i3-19https://pubs.cidrz.org/handle/123456789/12471In the context of NGO-led educational campaigns, the concept of sustainability is often related to the simple continuation of programmes after donor funding exhaustion. However, this project-based understanding obscures the institutional conditions that enable long-term functioning within public education systems. The article is based on a convergent mixed-methods inquiry conducted with six education-oriented non-governmental organisations and representatives of the Ministry of Education in Zambia to examine how educational interventions can be sustained amid resource volatility. Ordinal regression analysis shows that financial resilience and operational viability explain a substantial proportion of variance in sustainability strategies (Nagelkerke R² = .416). Whereas financial diversification can help mitigate funding shocks, governance coherence, monitoring architecture, coordination routines, and institutional alignment have a stronger structural impact on sustainability outcomes. Qualitative results also provide further insights into the fact that participation and capacity-building, despite their ubiquity, are often poorly embedded in the Ministry of Education's planning, budgeting, and performance-management systems. As a result, the research modifies a conceptual change between project continuity and institutionalised viability. Sustainability is redefined as system-level capacity that arises when feasible operational routines become institutionalised within structures of state governance and remain responsive under conditions of scarce resources. The article provides a clear explanation of why funding plurality is insufficient to ensure the endurance of programmes, drawing on the resource dependency, institutionalisation, and dynamic capability literature. Sustainability in resource-constrained educational systems is not realised through projects as independent entities, but rather through the institutionalisation of their operational logic in public systems. This reframing has significant implications for both NGOs, donors, and policymakers who hope to achieve enduring education reform within the funding period.https://doi.org/10.47191/ijsshr/v9-i3-19