Bhutan vaccinated almost all the adults in its population of 800,000 in a collective 16-day effort inspired by its king and culture -- and now has more adults who have received one dose than anywhere else in the world. Bhutan relied on advocacy, micro-level planning and its existing systems. Donated vaccines were transported in two donated refrigerated trucks. Volunteers trekked over difficult terrain to deliver equipment and share public health advice. Elders were vaccinated at home, and vaccine centers stayed open on weekends.