Vaccinations are one of our greatest public health successes to date, averting 2-3 million child deaths every year. They are one of the most cost-effective and evidence-based medical interventions available, and have caused a huge reduction in the global burden of infectious diseases.On top of this, vaccines bring social and economic benefits at both an individual and societal level. These include saving the costs of medical treatment and averting income or productivity losses, as well as avoiding the suffering of family and friends. There is also evidence of associations between vaccination and childhood developmental and educational outcomes, as well as broader evidence linking improved public health with lifelong productivity benefits and macroeconomic gains. Experts estimate that every $1 invested in expanding immunisation returns $60 in social, economic and environmental benefits.Yet vaccines still do not reach everyone. Globally, one child dies every minute from a vaccine-preventable disease. This is because 19 million children fail to receive their basic vaccinations before their first birthday each year. At Suvita, we believe that this is unacceptable. Half of the world's under-vaccinated children are in India. The country suffers the death of one child every four minutes as a result of a vaccine-preventable disease. This is despite India's early contributions to vaccine research and development and being a global producer of vaccines.We implement two evidence-driven solutions which have been found to increase uptake of vaccinations in India: building a network of carefully selected volunteer immunisation ambassadors, who share information with new parents in their community about local vaccine clinics; and sending personalised SMS reminders to caregivers informing them when their child is due for a vaccination.Emerging evidence suggests that a combination of both these methods is more effective and more cost-effective than either in isolation.