Salgado travelled at length in five different countries to photograph the international campaign, begun in 1988, to eradicate this global scourge. With the essential support of Rotary International and Unicef, he set out to tell how people live in the countries where polio is still a calamity and, above all, how, by what means and with what results the battle to defeat the disease is about to be won. His splendid black and white images hold the story of this great effort.