This company is a wholly owned subsidiary of the foundation Foreningen Realdania, which works for quality of life in the built environment. It owns and manages a collection of historic properties from the Middle Ages to the present, including Arne Jacobsen's own house in Charlottenlund, Friedenreichs Palæ in Viborg from 1757 and Priors Hus in Ærøskøbing. It also develops new construction, full-scale building experiments and areas together with municipalities and investors.
The properties are rented to private persons and companies. Members of the Realdania By & Byg Klubben club can visit the houses, get early notice of vacant rentals and join events and guided tours. Some properties hold open house events, sometimes free and without registration.
