Kathy and Bernard Murphy and family
Construction, Property
Rank 2017

Started in 1951 by John Murphy, who left his native Kerry for London in the 1930s, the civil engineering firm J Murphy and Sons employs 4,000 engineers and operates across the world, working on pipelines, tunnelling, bridges, power, rail and water projects, including London's Crossrail. The company, which has its headquarters in Kentish Town, north London, made €14.9m profit and showed €243.6m net assets in 2015. A separate property operation, Folgate Holdings, is worth €190.9m. Murphy worked until his death in 2009 aged 95 and the family is now headed by Kathy, 67, his second wife, and Bernard, 72, his Kildare-based son from his first marriage. We value the family at €406m.