The news emerged after the announcement of its 2003 results on Wednesday. Pre-tax profit was £16m, up 42% on the previous year. Turnover increased 20% to £650m.
Doughty said Costain intended to work for growth in the next 12 months.
Chairman David Jeffries said: "The strength of the business now allows us to take a more expansive look at the opportunities ahead and how we can best leverage these in the years to come."
Areas that Costain intends to target in 2004 include schools and nuclear decommissioning.