If polio eradication is a marathon — the vaccine was first introduced in 1954 — then the finish line is in sight in 2022, but this is the hardest part of the race. The places where polio still circulates are the hardest to reach and require the greatest care in implementing vaccine campaigns. But the end is in sight, and the investment case recently released by the Global Polio Eradication Initiative shows that the price tag to eradicate polio, US$4.8 billion for the next five years, is much less than if we don’t: “needless paralysis and death and an open-ended need for billions of dollars in additional costs.” Moreover, the lessons learned in polio surveillance, preparedness and response, and accountability and oversight strengthen health systems.