The late Eileen O’Byrne was one of Ireland’s most distinguished professional genealogists and was very highly regarded by her peers. She  worked in the field for almost four decades but most of her time was devoted to research for individual clients and consultancy; comparatively little of her work has been published. Eileen practised for some time at the Irish Bar before raising a family. She came to genealogy in the 1960s when she joined the Genealogical Office’s freelance research panel.

She was an active member of the Dublin Historical Association in its heyday, serving on its committee. She is a longstanding member of the Irish Genealogical Research Society (IGRS), the only membership organisation that existed in Irish ancestral research prior to the mid-1980s. Eileen O’Byrne, along with Eilish Ellis, was one of the senior figures behind the development of a framework for Irish professional genealogy. In 1980, along with other GO researchers, she was a founder of Hibernian Research, the first private sector genealogical company in Irish genealogy. She was also a founder member of AGI and served as its representative on the Taoiseach’s Task Force on Genealogy, one of the early precursors of IGL. Eileen was on the organising committee of the 1st Irish Genealogical Congress, which was held at Trinity College, Dublin, in 1991. She was the second President of AGI, serving in that capacity in 1998-2000.

Eileen was a contributor to Irish Genealogy: A Record Finder (1981), a landmark book which influenced later writing on the subject, and she edited the Convert Rolls (1981) for the Irish Manuscripts Commission. In the late 1980s AGI started to provide an advisory service on research in conjunction with the Genealogical Office. It evolved into the Genealogy Advisory Service, provided at the National Library and the National Archives. Eileen was one of the initial consultants in each. In 2005 she was elected a Fellow of the IGRS and at the end of the year became the second recipient of AGI’s Fellowship.