Fletcher and Francis La Flesche, her Omaha coworker and adopted son, divided the songs into three categories: religious ones, to be sung by a certain class either through initiation or inheritance; social ones, involving dances and games, always sung by a group; and ones to be sung singly, including dream songs, love songs, captive songs, prayer songs, death songs, sweat lodge songs, and songs of thanks. John Comfort Fillmore, a professional musician, added a "Report on the Structural Peculiarities of the Music."

Those interested in a vital aspect of Indian culture will want to own this book, which contains the musical scores as well as the native-language words for the songs.