The museum is meant to answer to art and not assert itself through architectural extravagance. Each gallery is defined through proportions, materials and excellent lighting. This lighting was a main element of design leading to the installation of a lightweight glass roof.
HdM replaced two of the older halls at Messe Bese with an extension that stacks 3 new ten meter high halls on top of one another, creating a sense of displaced volumes. The exterior cladding is brushed aluminum with the impression
Completed in 1998, the building was conceived as an organism and extends in multiple directions, reacting to the medieval lots, courtyard and structures surrounding it. The building shape was not formed from the outside but is a consequence of inner growth and building code restrictions. The building is clad in a unique bottle green cladding, with printing on it.