This symposium on provenance research and the restitution of Nazi-looted art was organized by the auction house Sotheby's and sponsored by the Muggenthaler International Genealogical Research Institute. After prior meetings hosted by Sotheby's on the same topic in London and Vienna, some 90 provenance researchers, art historians, government representatives, lawyers, and academics met in Amsterdam to discuss the Dutch restitution regime in particular and, in general, the progress made since the passing of the Washington Principles on Nazi-looted art in December 1998.