 Born in Gorizia, Italy to Slovenian parents, Mozetich moved to Hamilton, Ontario in 1952, where his father found work as a machinist.He started his musical training by studying piano, and later studied composition with Lothar Klein and John Weinzweig at the University of Toronto, from which he received an Associate of the Royal Conservatory of Toronto Diploma in 1971 and a Bachelor of Music degree in 1972 in composition and piano.With the help of the Canada Council he then continued his musical studies in composition privately in Rome, Siena and London with Luciano Berio, Franco Donatoni, and David Bedford.