Underlying pre-tax profits at design, engineering and project management consultancy WS Atkins rose by 18.4% to £164.6m in the year to the end of March.
The group continued to improve its underlying operating margin along with revenue that rose 11.8% to £2.08bn (2016: £1.86bn) up 4.3% on a constant currency basis.
Underlying operating profit increased 15.7% to £171.5m (2016: £148.2m), at an improved underlying operating margin of 8.2% (2016: 8.0%).
Operating cash flow in the year was £100.4m (2016: £116.1m), representing 65.2% (2016: 81.0%) of operating profit on a reported basis.
Chairman Allan Cook and chief executive Prof Dr Uwe Krueger said: "We delivered a strong set of results this year with underlying profit before tax improving by 18.4% to £164.6m.
"Our underlying operating margin continued to improve and we delivered revenue growth on a constant currency basis of 4.3%, underpinned by the acquisition of PP&T in 2016.
"We believe that the Group is in a strong position to execute on its growth strategy going forward."