PW Joyce’s final and most extensive music publication appeared in 1909: Old Irish Folk Music and Songs: A Collection of 842 Irish Airs and Songs Hitherto Unpublished (Dublin: Royal Society of Antiquaries of Ireland; London: Longmans, Green & Co, etc.).

It is presented in four sections: 1 The Joyce Collection (melodies collected and recollected by himself, or sent to him in manuscript from all parts of Ireland); 2 Continuation of the Joyce Collection (Irish folk songs in the English language, with the words set to the proper old Irish airs, the syllables under the notes; most from his childhood recollection, and from his personal collection of ballad sheets); 3 The Forde Collection (selection of melodies collected by William Forde of Cork, 1830s–1850s, edited by Joyce); 4 The Pigot Collection (selection of melodies collected by John Edward Pigot of Dublin, 1840s–1860s, edited by Joyce). The two latter collections had been given to Joyce by relatives of Pigot; in 1910 he donated them to the Library of the Royal Irish Academy where they remain.