Since 2003, Koller Auctions has been holding auctions of tribal art in close collaboration with Jean David, specialist and owner of Galerie Walu in Zurich. Many important artists from the early 20th century, such as Picasso and Braque, E.L. Kirchner and Alberto Giacometti, Derain and Vlaminck, were inspired by sculptures from black Africa and owned collections themselves, some of them quite important.