The Baker & McKenzie team advised GMC on the deal, led by corporate partner Richard Lustig and associate Narelle Thomas. They with corporate adviser Eaton Square and accounting firm KPMG.
Lustig said the combination of the two companies will enable SMEC to diversify into the resources industry and enter new geographical markets in North and South America.
"The merger of these two leading service providers creates exciting potential for the continued global expansion of the consolidated group's operations," he said.
With over 170 personnel, GMC has operations in Australia, Canada, Chile, Singapore and the USA. SMEC provides high quality consulting services for major infrastructure projects.
SMEC was advised by Minter Ellison and ANZ Banking Group Ltd.