Irish Script on Screen (ISOS) is a project of the School of Celtic Studies, Dublin Institute for Advanced Studies. The project was launched in 1999 and continues to pursue its objective of making Ireland's native tradition of manuscript production available, free of charge, via a dedicated website (www.isos.dias.ie). Partnerships are developed with repositories of Irish manuscripts, and these partnerships are central to the collaborative spirit of the project.

Manuscripts on the site are representative of both the vellum and the paper traditions, and date from the earliest surviving manuscript in Irish (Leabhar na hUidhre) to manuscripts produced at the end of the tradition in the 19th century. Earlier liturgical manuscripts such as the Domhnach Airgid and the Stowe Missal (both in the RIA), and the Psalter of St Caimín (Franciscan Collection, UCD) are also displayed, as are manuscripts from other traditions such as the National Library Manuscript of Giraldus Cambrenisis.

One of the thematic components of the ISOS site is that of medieval and early-modern Irish medicine. No area of native learning greater illustrates contact with European traditions than Irish medical writing. Many manuscripts survive that bear witness to this, and ISOS has been privileged to digitise and display some of the most important of these, from the collections of NUI Galway, the RIA, Trinity College Dublin, and the National Library of Ireland.

The textual range of the non-medical manuscripts extends from early sagas and legal texts to the poetry of the late 18th century. ISOS contains different recensions of Táin Bó Cuailnge, the central text of the Ulster sagas created around the hero Cú Chulainn. Genealogies (particularly the collection of An Dubhaltach Mac Fhir Bhisigh, in UCD) and historical material such as collections of various annals are also displayed. The literature of the Early Modern period is well represented, particularly in the area of bardic poetry, with a number of important family poem-books ('duanaireadha') available on the ISOS site. The later poetic tradition is in evidence through the work of 18th-century scribe-poets such as Seán Ó Murchadha, Aodh Buidhe Mac Cruitín, Donnchadh Ruadh Mac Conmara, and Piaras Mac Gearailt (NUI Maynooth).

ISOS is a long-term project which continues to evolve. Seminars and lectures on the subject of digitisation and electronic display are regularly organised by the project at the School of Celtic Studies. On the ISOS website, catalogue descriptions accompany the displayed manuscript pages, and it is intended to add further content in the form of transcripts and editions as the project progresses. It is also intended to expand the collaborative base of the project through the creation of new partnerships over time.