Ivan Spassov is one of the premiere Bulgarian composers and conductors of the 20th century. He systematically integrates elements of the rich Bulgarian folklore into his music. His style also exhibits influences from the contemporary Western European compositional tradition. The mastery of his craft shines in the use of aleatoric technique, cluster harmonies, and polyphonic elements, uniquely combined with the rhythmic, melodic, and modal intricacies of the Bulgarian folklore. This book examines Spassov s songs for women s choir, in the Bucolics From The Pirin Region collection, and how they relate to their original folk versions. Areas of study include a brief examination of Bulgarian musical folklore in relation to the uniqueness and inter-regional influences of the rhythm, meter, mode, melody and text, and an analysis of the musical scores. This analysis should provide evidence that Bucolics From The Pirin Region are examples of late-twentieth-century musical art that remain typically Bulgarian and preserve the individuality of the traditional folklore, and should be particularly useful to conductors, music educators and anyone else interested in multicultural choral music.