Folksong arrangements hold a significant place in Béla Bartók's oeuvre: more than a third of his compositions are folksong arrangements or contain movements built on folk music material. Moreover, the genre is not confined to certain style periods; it is present throughout Bartók's career. This catalog brings together all the folk melodies that appear in Bartók's compositions. They were selected from the documents of his ethnomusicological work: from the music books used in his collecting trips, from the master sheets containing his notations from phonograph recordings, and, occasionally, from his published collections. All the data pertaining to the original performances of the melodies - the singers' or performers' name, age, the place and time the song or instrumental piece was recorded, the collector's name in case it was not Bartók - can be found in the commentaries accompanying the melodies in the catalog. The accompanying CD contains all available surviving original recordings of the melodies.