The Cantonal Parliament was built in the 16th century and most of its original load-bearing structure has been preserved. The building is nowadays protected as a historical monument and has hosted since its construction the legislature of the city and canton of Fribourg. The project consists of transforming and renovating the building while enhancing its service conditions, enlarging the current spaces and creating a new vertical circulation. An innovative reinforcement system is used to reduce the large deflections of the timber structures and to prevent subsequent deformations. Such interventions are highlighted with elegance.