Due to the status of its builder, Doune reflected current ideas of what a royal castle building should be. It was planned as a courtyard with ranges of buildings on each side, although only the northern and north-western buildings were completed. These comprise a large tower house over the entrance, containing the rooms of the Lord and his family, and a separate tower containing the kitchen and guest rooms. The two are linked by the great hall. The stonework is almost all from the late 14th century, with only minor repairs carried out in the 1580s. The restoration of the 1880s replaced the timber roofs and internal floors, as well as interior fittings.