The fifth Sonsbeek differs from the previous triennial editions in a number of ways. First, for the first time, the working committee responsible for selecting artworks is made up half of people from art institutes and half of sculptors. In the run-up to the exhibition, they face new challenges. For instance, in selecting artworks, they have to take competition into account: the Venice Biennale in 1964 and 1966. A bigger challenge is the ambition to give a more convincing overview of contemporary developments in sculpture compared to previous editions. This proves a complicated task, as all kinds of new movements manifest themselves in the 1960s.

What the artists have in common is that they are trying to bring art out of "its lofty isolation", according to Dutch proffessor Hans Jaffé in the catalogue's introduction. The boundary between viewer and artwork blurs both literally - pedestals disappear - and figuratively. This gives artists more freedom to experiment with new techniques and materials. Sonsbeek '66 shows a greater variety of sculptures, in terms of materials, techniques and styles.