This study challenges the prevailing horizontal conceptualization of social capital by documenting a vertically concentrated form of relational power within elite Thai secondary schools. While Western administrative models emphasize distributed leadership and polycentric governance, this research uncovers a tightly centralized architecture of institutional permeability. Using an explanatory mixed-methods design—integrating forensic access logs ( ) and 66 in-depth interviews—we investigate the structural mechanisms that govern school-environment interactions. Findings reveal a decisive Gatekeeper Effect: formal bureaucratic protocols for school access achieved a success rate of only 13.6%, whereas informal, Director-mediated referrals achieved a 100% success rate. This empirical disparity demonstrates that de jure state authority has been functionally displaced by the de facto, trust-based networks of school leadership. We theorize the School Director as a "Catalytic Hub," the indispensable relational node who converts symbolic capital (Baramee) into kinetic network activation. This hub-and-spoke topology facilitates exceptional operational agility but induces a paradox of "Fragile Efficiency"—a system optimized for high performance yet acutely vulnerable to "Succession Shocks." This article contributes to social capital theory by proposing a model of Concentrated Relationality and advances leadership theory by deconstructing the "Catalytic Hub" as a prerequisite for service delivery in fragile state contexts.
BHROMKHOCH Thiradech (2026) studied this question.