The main scope behind this thesis is to examine the Bernadotte library at the Royal Castle in Stockholm, in its function as an institution of the cultural heritage, research library and museum. This unique combination constitutes an interesting object of research. It is a field that needs to be examined. The Bernadotte library is a unique example of a library museum. The thesis has been accomplished through a narrative study of literature. The thesis shows that the Bernadotte library today is a living example of a good combination of respect for the cultural heritage, an effective research library and a unique museum.