Early stage design work has started on upgrading the A96 between Inverness and Nairn to dual carriageway and building a bypass for Nairn.
Transport Minister Stewart Stevenson said the project included a new road to link the A96 to the A9 south of Inverness.
He said the study would identify how the schemes could be progressed.
The £500,000 contract has been awarded to Jacobs Engineering UK and its findings are expected in spring 2011.
Mr Stevenson said: "The Scottish government is determined to improve the main route between Aberdeen and Inverness, the two biggest economic centres of the North.
"This contract underlines our commitment to the communities and businesses this vital link serves."
He added that upgrading the A96 would reduce journey times and ease travel in and around the east of Inverness, improve access to Inverness Airport and help development between the city and Nairn.
The study forms part of the government's Strategic Transport Projects Review and wider efforts to upgrade trunk roads in the north and north-east.
Construction started in February on the £31.5m Fochabers-Mosstodloch bypass, which is also on the A96 route between Inverness and Aberdeen.
But plans to build a £400m bypass for Aberdeen have been delayed by a legal challenge.