Indonesia’s government has chosen an unorthodox vaccination strategy: immunising people between the ages of 25 to 55 before the older, more vulnerable population, with the aim of achieving herd immunity. How do we understand the priorities of our national plan and gaps in the National Covid-19 Immunisation Programme. Melisa Idris and Sharaad Kuttan speak to Dr Khor Swee Kheng, Consultant in Public Health Policy & Systems.