Nevertheless, Zubillaga’s music does not only intend to re-enact highly charged emotional inner landscapes, but also envelops his political militancy and the cultural struggle of 20th-century Latin America.
Notable works from his first period (1961–1966) include "Haiku", "Passages in Fluctuation", both for solo piano, "Directions" for String Quartet, as well as "Music for 10 Instruments" for the film El Huerco (Hell).
The turning point arrived in 1967, with his music taking on more expressive nuances of the imagery, such as the effects of "Ambientes" for solo piano, composed in 1967.
His third period began from 1970 when his music becomes more improvisatory, perhaps due to his experiences playing in the Group of Improvisation (Grupo de Improvisacion) with Enrique Gerardi and Jorge Blarduni.
Music from this final period often reminiscence on events or places from the past with titles like "That Afternoon in That House" and "Once…" Two other pieces were dedicated to his wife and one to his son; the latter has yet to be performed.
The piece Ongilash (1964) will receive her posthumous premiere on Friday 5 October 2012 by the National Symphony Orchestra (Orquestra Sinfonica Nacional) at the Auditorio de Belgrano, Buenos Aires.