Internationally recognized as a pioneer of Latin-American musicology, the role of Francisco Curt Lange as an active promoter of the musical avant-garde has been nearly ignored by musical research. The article studies the function that contemporary music plays within the main projects of his campaign Americanismo musical: the Boletin latino-americano de musica and the Editorial Cooperativa Interamericana de Compositores. The conception of musical avant-garde as an international phenomenon, present in these projects, is interpreted in relation to Lange's americanist goals and the transnational ideal that characterizes them.