Junction upgrades on Plymouth Road will begin on Tuesday.
The much anticipated Eastern Corridor Junction Improvement Scheme kicks off with work at Marsh Mills roundabout and at the Larkham Lane junction.
Cones will go out on the road on Tuesday and lane closures will be in place between 9.30am and 5.30pm.
At Marsh Mills, an extra lane is being added to the entry of the roundabout for traffic accessing the A38, with upgrades to the crossing facilities and signals.
So this work can be done, there will be a lane closure on the approach to the roundabout.
Meanwhile, Larkham Lane will be changed to a two lane exit, allowing more vehicles to flow onto Plymouth Road in a shorter green light window.
A new crossing will be added here too, and that is where work will begin on Tuesday with a lane closure on the inbound Plymouth Road carriageway.
Work at Cot Hill where the road will be widened, Coypool Road, Woodford Avenue, Dingle Road and Glen Road will follow later in the year.
The improvements are all part of the wider Eastern Corridor Junction Improvement Scheme and follows on from work already completed at the Cot Hill and Merafield Road junction earlier in the year.
More information on the scheme can be found at www.plymouth.gov.uk/ecjis