Phase 1 of the carriageway works on Lothian Road between Rutland Street and Bread Street begins this evening.
The thoroughfare will be closed in 7 separate phases with the first phase focusing on the southbound lane between Lothian Road and the West Approach Road.
That section of road will be closed to traffic between 7pm this evening and 7am for the next five nights.
Castle Terrace will be closed except for local access, while traffic heading southbound between Princes Street and Lothian Road will be diverted via Shandwick Place.
Phase 7, which involves improving footways and crossings around the Usher Hall, is scheduled to be complete by 28 April.