Improvement work to start on A82 at Crianlarich
Transport Scotland has published its shortlist for the £5.5m Crianlarich bypass construction contract.
It has also announced its intention to award a £2m design contract for improvements to a nearby stretch of the A82, from Tarbet to Inverarnan.
Five construction companies have been invited to bid for the work at Crianlarich.
Transport Minister Keith Brown said the A82 was a "vital economic and social lifeline".
The construction of the Crianlarich bypass will begin this summer and is scheduled to finish 12 months later.
The companies shortlisted for the work are Balfour Beatty, John Paul Construction, RJ McLeod, I&H Brown and Graham Construction.
Design work on the 10 mile (16km) section of the road from Tarbet to Inverarnan will begin this month and is expected to take two years.
It will be carried out by a Halcrow Fairhurst joint venture.
Mr Brown said: "This government is firmly committed to upgrading the A82, as seen by our recent announcement on the Pulpit Rock works starting later this month.
"Our recognition of the A82 as a vital economic and social lifeline, means, through local consultation, we have developed a programme of road closures that will have less impact on road users, local residents, businesses and visitors."