In 1952, Berio went to the United States to study with Luigi Dallapiccola at Tanglewood, from whom he gained an interest in serialism. He later attended the Internationale Ferienkurse für Neue Musik at Darmstadt, where he met Pierre Boulez, Karlheinz Stockhausen, György Ligeti and Mauricio Kagel. He became interested in electronic music, co-founding the Studio di fonologia musicale, an electronic music studio in Milan, with Bruno Maderna in 1955. He invited a number of significant composers to work there, among them Henri Pousseur and John Cage. He also produced an electronic music periodical, Incontri Musicali.
In 1960, Berio returned to Tanglewood, this time as Composer in Residence, and in 1962, on an invitation from Darius Milhaud, took a teaching post at Mills College in Oakland, California. From 1960 to 1962 Berio also taught at the Dartington International Summer School. In 1965 he began to teach at the Juilliard School, and there he founded the Juilliard Ensemble, a group dedicated to performances of contemporary music. In 1966, he again married, this time to the noted philosopher of science Susan Oyama (they divorced in 1972). His students included Louis Andriessen, Steven Gellman, Dina Koston, Steve Reich, Luca Francesconi, Giulio Castagnoli, Flavio Emilio Scogna, William Schimmel and Phil Lesh of the Grateful Dead.