The Liturgical chant bibliography 24 retains the traditional format: (1) Editions and facsimile editions, (2) Books and reprints, (3) Congress reports, (4) Chant journals, (5) Colections of essays and dictionaries, (6) Articles in periodicals and Festschriften. Additions to the bibliographies of previous years (mostly reviews) are listed directly after this introduction. This year's bibliography opens with five Cantus planus databases and indexes, which were introduced in a detailed review published in the Journal of the American Musicological Society, 67 (2014), 267–85 (24001).