This special issue of Plainsong and Medieval Music honours the memory of Michel Huglo (1921–2012) with four articles that resulted from two sessions of papers held on 11 May 2013 at the 48th International Congress on Medieval Studies at the University of Western Michigan. Titled ‘Chant and Liturgy: Papers in Memory of Michel Huglo’, the sessions were organised by Anna Grau, Cathy Elias and Daniel DiCenso, with papers given by Terence Bailey, Frank Lawrence, Rebecca Maloy (in collaboration with Emma Hornby), William P. Mahrt, Nils Holger Petersen and Michael Norton. Also included is a bibliography of Michel Huglo's articles and unpublished papers to 2012, complementing earlier bibliographies. Obituaries are also cited. Each article in this volume advances research on subjects that occupied Michel Huglo fully at different times in his life.