The major research focus area in Celtic Studies is comparative Celtic philology, historical Celtic phonology and medieval Celtic languages and literatures with particular focus on Old and Middle Irish and Welsh. Manuscript sources, genre and the editing of early Irish texts is an area of expertise as is the linguistic study of Modern Irish.

In 2004-2006 the Celtic Section has been actively involved as partner in an EU funded project entitled Celtic, Regional and Minority Languages Abroad Project (CRAMLAP). With partners from Norway, Republic of Ireland, UK, France and Germany the project has produced a number of research papers at international conferences, organised an international symposium in London in 2006 and has a web-page http://www.cramlap.org

Staff working in this research area include Gordon Ó Riain.