This thesis presents a critical edition of the Anglican cathedral works of Irish-born composer Sir John Andrew Stevenson (1761-1833). It evaluates his contribution to that repertoire and the inclusion of his works in the programmes of various cathedrals throughout Ireland and the United Kingdom. Consideration will also be paid to Stevenson’s place alongside his contemporaries and to the popularity of his works throughout the nineteenth century. Various criticisms of the composer’s works will be explored. The first chapter of the thesis outlines Stevenson’s biography, focusing on him as composer both of secular and sacred music. The second chapter looks at conditions in the Dublin cathedrals c.1800. Chapter three focuses on external influences on Stevenson’s compositional style, including the music of Haydn; it also appraises Stevenson’s legacy and establishes him as a prolific composer whose contribution to the repertoire of Irish cathedral music was of notable importance. A number of primary sources exist for Stevenson’s cathedral works. These are considered in the second part of the thesis, which also describes the process of editing and dating the compositions following analyses of primary sources with textual commentaries. The third part of the thesis presents a critical edition of all of Stevenson’s cathedral works. The rationale behind the preparation of this edition stems from the paucity of critical editions of Irish cathedral music in general. To date the following remain the only exercises in critical editions of the works of Irish cathedral composers: Barra Boydell’s editions of selected anthems from the repertoire of Christ Church Cathedral Dublin (1998), Gillen and Johnstone’s A Historical Anthology of Irish Church Music (2001); Douglas Gunn’s editions of individual cathedral works by Thomas Carter (c.1740-1804), Daniel Roseingrave (1650-1727) , Ralph Roseingrave (c.1695-1747) and Richard Woodward (1743-1777); and various unpublished editions prepared as MA theses, including those studies by Carol Cunningham (1997), Eithne Donnelly (1998), Elaine Sherwin (2000) and Nicola Horn (2004). As an initial step, the number and titles of the anthems.