Amec reported a 7% jump in pre-tax profit to £113m for the year ending 31 December 2003, compared with £105m in 2002, and said two-thirds of operating profit was from its services and investments divisions.
Peter Mason, the chief executive of Amec, said that with the increased income the company would continue to migrate to higher value work.
He said: "These results confirm the transformation of our business from traditional construction to engineering services." Amec's turnover increased 9% to £4.7bn from £4.3bn a year ago.
Alfred McAlpine signalled that its shift to a services-based company was complete. The firm has made seven bolt-on acquisitions in the past three years, and as with Amec, two-thirds of its business is in the services sector.
McAlpine reported that its pre-tax profit was up 20% to £36m for the year ending 31 December 2003, compared with £30m in 2002. Turnover increased 13% to £869m from £768m.
Chief executive Ian Grice said the company was achieving the performance it promised in 2003 and that the seven acquisitions made between 2001 and the end of 2003 were adding value.
He added: "This is delivering visible, long-term, low-risk earnings and positioning us in large growing markets that offer strong margin potential."
McAlpine's order book has also increased to £3bn from £2.6bn in 2002, which has produced revenue streams stretching out beyond 2010.
Amec has also won a £277m contract to rebuild Iraq's power supply, the biggest deal won by a British firm so far, in partnership with the San Francisco-based engineer Fluor.
The power deal is one of 10 major Iraqi design-and-build contracts, paid for by the US government, that are due to be announced in the next few weeks.