Donegal families are a mixture of native Gaelic families, and of Scots-Irish families who came to Donegal from the 17th century onward. Common names in the county include O'Neill, O'Donnell, Bonner, Barr, Bradley, Duffy, Friel, Gormley, O'Kane, Gallagher, Harkin, McBride, McCafferty, McDaid, Patton, Morrissey, Ward and Sweeney. It is also one of the counties which experienced a high level of emigration to North America and elsewhere. This book sets out the records available for Donegal, where they can be accessed, and how they can be used to best effect in tracing Donegal families.