For the Tamil Nadu Climate Change Mission (TNCCM), IIHS is undertaking a comprehensive project to assess and rank the climate and environmental performance of all 38 districts and 25 large cities in Tamil Nadu. IIHS is developing a robust, quantitative Green and Climate Index (GCI), using indicators such as green cover, water resources, renewable energy, waste management, and socio-economic factors. The project includes detailed case studies, an interactive web platform for data visualisation and benchmarking, and tailored feedback and advisory support for districts. This initiative aims to foster evidence-based policy, peer learning, and capacity building, ultimately supporting Tamil Nadu’s sustainable development and climate resilience goals.