Owing to the particular fragility of Paul Klee’s works, the way they are exhibited differs from that of conventional permanent displays, where the same works are on view to the public year after year.

The delicate state of Klee’s pictures is an outcome of the way he worked: he was fond of experimentation – not just in terms of form and content, but of technique, too, and used watercolours and blends of pigment and glue, inks and papers that were and are highly sensitive to light. If these were exposed to the light for too long, the colours would gradually pale and the papers turn brown and become brittle – this despite the attenuated lighting levels of between 50 and 100 lux in the Zentrum’s galleries and the use of special glass that absorbs much of the particularly damaging UV radiation. As a way of coping with the problem the collection display, especially where works on paper are concerned, is rotated every six months or so. The conservational principle underlying the Zentrum Paul Klee’s collection calls for items that have been on show for an extended period to be “rested” in the Zentrum’s stores under strict lighting, temperature and humidity conditions.

There are also conceptual and logistical reasons for regularly changing the works on show. The Zentrum Paul Klee’s 1750 m2 exhibition space, large as it is, could in no way cope with displaying at once all 4000 or so of the oils, watercolours and drawings it has in its possession. Rotation also gives an opportunity for regularly revealing fresh – and on occasions, unexpected – aspects of Paul Klee’s oeuvre by changing thematic focal points and references, and for offering visitors the chance to experience his lesser-known works and series.