The firm announced last November that founder and majority shareholder Ray O’Rourke will be stepping down as CEO in September.
He will be succeeded by Seamus French who started in his new role as Europe Hub MD and CEO-designate on Monday.
Welcoming him O’Rourke said: “I am delighted to welcome Seamus to the business and look forward to working with him over the coming months to ensure a smooth CEO transition.
“He is a world-class executive, and his strong plc background and experience of leading international operations will help us continue to improve our performance and deliver long term growth.”
French added: “It’s an honour to have been appointed by the Board to lead this business and I cannot wait to get started.
“As a non-executive director, I’ve been hugely impressed by the Laing O’Rourke team, its technical and engineering expertise, strong order book and vision to transform construction and build safely and sustainably.
“We have exciting ambitions and great opportunities ahead of us, as we continue to innovate and redefine how this vital industry delivers the buildings and infrastructure that people and communities need.”