Mouchel Parkman, with a combined staff of 4000, says its main market is providing high value commercial, financial and technical expertise to clients in the public sector.
The new firm hopes the merger will enable it to scale up operations in highway engineering and in infrastructure and asset management across a wide range of sectors and put it in a better position to compete for larger commissions - including those with an element of private sector investment.
While there were clearly big cultural differences to overcome in bringing the two together, there was a fair amount of common ground. Both, for instance, were relatively newly-floated and listed on the stock market - Parkman in 2001 and Mouchel in 2002.
Both are more than a hundred years old. Parkman, founded in 1888, is 11 years older than Mouchel.
Mouchel Parkman is aiming for 20% year on year growth for the next few years. According to Jonathan Gammon, there is no reason why the geotechnical division shouldn't keep pace.