Fragmented, sector-by-sector governance is poorly suited to cascading risks that couple climate, food, water, health, biodiversity, soils, energy, and environmental quality. This paper addresses the translation gap between integrative security–sustainability paradigms and the routine machinery of government, including planning, budgeting, procurement, and accountability. We develop the Spheres of Security (SOS) model as a conceptual–operational method organised around four overlapping spheres (biophysical, economic, social, and governance) and a repeatable cycle—diagnose → co-design → deliver → demonstrate → adapt—illustrated through two stylised vignettes (urban heat and health; watershed food–water–energy). SOS introduces an auditable overlap rule and an Overlap Score, supported by lean assurance, to make verified multi-sphere co-benefits commissionable and to surface trade-offs transparently within normal, accountable institutions (consistent with weak securitisation). We provide implementation guidance, including minimum institutional preconditions and staged entry-point options for jurisdictions where pooled budgets and full administrative integration are not immediately feasible.
Park et al. (Mon,) studied this question.