Regional Air Quality Governance Gaps in South Asia India's metropolitan air quality crises reveal a structural problem: pollution doesn't respect municipal boundaries. The National Capital Region's severe winter smog (regularly exceeding 400+ AQI) originates 40-60% from sources outside Delhi—crop burning in Punjab/Haryana, industrial emissions from Uttar Pradesh, and vehicle pollution from neighboring states. Bombay High Court's directive mirrors similar findings from WHO studies showing transboundary pollution accounts for 30-50% of urban air degradation across South Asian cities. This matters because siloed municipal regulations fail; effective air quality requires coordinated regional emissions standards, cross-state enforcement mechanisms, and shared monitoring infrastructure—a model most developing democracies still lack.