[2][3] Many famous performers, such as Teresa Berganza, Martha Argerich, Gidon Kremer, José Carreras, Kiri Te Kanawa, Patricia Caicedo, Bernarda Fink, Cecilia Pillado, María Isabel Siewers, Jorge Chaminé, Agathe Martel, Karina Gauvin,Julie Nesrallah and José Cura have included works of Guastavino on their programs or recordings.

During these years, the BBC Symphony Orchestra premiered the orchestral version of his Tres Romances Argentinos, under the baton of Walter Goehr.

[3][6] Guastavino's musical style marked a stark contrast with the works of his 20th-century Argentine contemporaries such as Alberto Ginastera and reveals the influence of European composers such as Albéniz, Granados, Rachmaninoff, Chabrier, Falla, Debussy, and Ravel, but also is clearly inherited from the luminaries of 19th-century Argentine nationalist composers, such as Alberto Williams, Ernesto Drangosch, Francisco Hargreaves, Eduardo García Mansilla and Julián Aguirre.

Guastavino's stylistic isolation from the modernist and avant-garde movements going on around him, and the self-consciously nationalist content of his songs made him a model for Argentine popular and folk musicians in the 1960s.

The poets whose works he set to music included Rafael Alberti, Leon Benarós, Hamlet Lima Quintana, Atahualpa Yupanqui, Pablo Neruda, Gabriela Mistral, and Jorge Luis Borges.