This monograph on Renaissance music is devoted to discussing more than 150 compositions which involve symbolism inspired by ideas and themes inherent in the musical culture of the time. The introduction describes the historical and theoretical premises of the use of the terms "allegory", "sign" and "symbol", and goes into the aspect of number symbolism as well as the aims, limits and principles of musico-symbolical analysis. Other studies which concentrate on Dufay and Josquin, deal with the symbolical application of "soggetto ostinato" and canon technique, or treat such themes as music for the dead and the Holy Virgin. The final study is about the conception of heavenly music and musical composition. The text includes musical examples, and indexes of compositions and names.