The win comes just weeks after Castle launched its new East Kilbride regional office.
Castle will start on site in January at the Caol Joint Campus – a primary education facility and community centre being built for Highland Council.
Derek Reid, Castle’s director responsible for Scotland, said: “I’m delighted to announce our appointment to such an important project as the new Caol Joint Campus and community centre scheme.
“With a number of major education contracts successfully completed to our credit, coupled with our established working relationship with Kier Construction, I am confident that we will deliver this project to the high standard that clients have come to expect when working with us.
“In keeping with our company ethos throughout delivery of this project we will employ local labour and engage with local subcontractors, as well as call upon the local supply chain at every opportunity.”
M&E work will be delivered in two phases – the first of which is scheduled to last 16 weeks, while the second phase will take 26 weeks to complete.
Kier Construction’s area operations director, Sean O’Callaghan, said: “Kier is delighted to be working with Highland Council and Castle Building Services on such an important scheme for the Fort William area. With construction due to start soon we are on track for the schools anticipated opening in July 2016.”