FitzGerald was educated at the University of British Columbia in Canada and Harvard in the United States. He worked at the Victoria and Albert Museum in London, in the furniture department. He later returned to Ireland, and became active in conservation issues, becoming involved with the Irish Georgian Society and at this time he was appointed its president in 1991. His daughters are Catherine (Countess of Durham, married to Lord Durham), Nesta and Honor. He has represented the art auctioneers Christies in Ireland. His knighthood must pass to a son, not another male or female relative, and since he has none, he will probably be the last Knight. Desmond FitzGerald currently resides between Glin Castle, County Limerick (which he inherited as a child) and his Dublin townhouse.