eVIN is an integrated package of people, processes and product. It is a combination of IT infrastructure and trained human resource to enable real-time monitoring of stock and storage temperature of the vaccines kept in multiple locations across the country. Our team was instrumental in gathering requirements and doing functional analysis of the system in collaboration with various government departments and stakeholders. The system has been implemented in all 731 districts, across 36 states and union territories and achieved over 80% reduction in instances of vaccine stock-outs and ensured improved availability of adequate and potent UIP vaccines with vaccine availability rate of over 99% at all cold chain points.