Lebič's early style was fairly traditional, but his work from after 1965 demonstrates the influence of the European avant-garde. The opening of Slovenia to foreign travel in the 1950s and 60s allowed for greater musical and cultural exchange with the rest of Yugoslavia and Europe, encouraging the development of a Slovenian avant garde. Lebič's 1965 works Meditacije za dva for viola and cello and the cantata Požgana trava are examples of his use of new melodic and vocal techniques. Later, he developed a style that balanced respect for traditional culture with cosmopolitan modernism.