Danish engineering giant Cowi has bought ground engineering and tunnelling specialists Donaldson Associates.
Cowi said the acquisition strengthened its underground engineering skills base, and widened it to include caverns, hard rock, spray concrete lining and micro tunnelling.
Donaldson currently employs 143 people across five UK offices and one in Hong Kong.
Continuing to operate as Donaldson, it will work with Cowi tunnel and underground centres in Denmark, Qatar, India and the US as well as in the UK alongside Cowi bridge subsidiary Flint & Neill.
Cowi chief executive Lars-Peter Søbye said: “The acquisition of Donaldson Associates is a major achievement for Cowi, and is in line with our growth strategy.
“We have complementary market coverage, and together we will be one of the world’s leading engineering consultancies with a large, highly qualified, pool of specialists who are able to bring significant strength and expert skills to our customers around the globe.”