Reilley joined WSP as deputy CEO – UK & Ireland, two and half years ago from Stanec UK where he was managing director for infrastructure and buildings.

Before that he spent 14 years of his career at Peter Brett Associates.

In his new role, Reilley will drive WSP’s strategic priorities and client delivery, reinforcing the firm’s capabilities in critical growth markets, including infrastructure, environment, water, property and energy.

His promotion to the top coincides with the appointment of Mark Naysmith, currently president for WSP’s EMEIA region, to global chief operating officer, also effective from January.

With over 35 years at WSP, Naysmith will drive growth, financial performance, and collaboration across WSP’s regions worldwide.

Mark Naysmith, President EMEIA, said: “After 36 years at WSP, it has been a pleasure to lead the EMEIA region.

“Paul’s understanding of our UK and Ireland business and his commitment to client success make him an outstanding choice to take the reins.”