The Oxford Dictionary of Family Names of Ireland contains more than 3,800 entries covering the majority of family names that are established and current in Ireland, both in the Republic and in Northern Ireland. It establishes reliable and accurate explanations of historical origins (including etymologies) and provides variant spellings for each name as well as its geographical distribution, and, where relevant, genealogical and bibliographical notes for family names that have more than 100 bearers in the 1911 census of Ireland. Of particular value are the lists of early bearers of family names, extracted from sources ranging from the medieval period to the nineteenth century, providing for the first time, the evidence on which many surname explanations are based, as well as interesting personal names, locations and often occupations of potential family forbears. This unique Dictionary will be of the greatest interest not only to those interested in Irish history, students of the Irish language, genealogists, and geneticists, but also to the general public, both in Ireland and in the Irish diaspora in North America, Australia, and elsewhere.