In 1960s, prior to her fame and international acclaim, Mercedes Sosa defied expectations by drafting, together with four other young musicians, the "Manifesto del Nuevo Cancionero" ("The New Songbook Manifesto"). How did this manifesto make an impact on youth culture in Argentina and future generations of Latin Americans? How much did the "Nuevo Cancionero" influence the development of the "Nueva Trova Cubana," the folk-music revolution driven by its message of social and political change? How did Sosa's ideology affect the politics of both emerging and developed countries? Apart from the millions of records she sold, the thousands of international concerts, her countless fans and detractors, Mercedes Sosa left behind an indelible legacy, an ideal that has not become a reality yet but which keeps pushing forward. Mercedes Sosa, The Voice of Latin America is an intimate and informative journey into the world of a ground-breaking artist and activist.