Network Rail has awarded Bam Nuttall a £10 million contract for upgrade works on the Highland mainline.
The contract involves extending platforms 1 and 2 at Pitlochry station and carrying out modifications to extend the track layout.
Infrastructure works will also be carried out at Aviemore station to extend the loop to its north.
Signalling systems at Pitlochry and Aviemore will also be altered and upgraded as part of the project.
Transport minister Humza Yousaf said: “The works planned to take place at Aviemore and Pitlochry allow for far more efficient crossing of trains, which along with the soon-to-be-introduced HSTs and infrastructure enhancements, will deliver faster more frequent journeys between Inverness and the Central Belt.”
Bam Nuttal regional director Jerry Dickson added: “Our team will be looking for opportunities to work with the local community to identify opportunities to leave a positive lasting legacy from the work at both stations.”