In May 1994, the Intergovernmental Committee for Promoting the Return of Cultural Property to its Countries of Origin or its Restitution in Case of Illicit Appropriation recommended that the Director-General of UNESCO be invited to have specialised studies made by experts to clarify issues in cultural objects that are disputed or unclear. Collectors (both public and private), dealers, archaeologists, conservators and other specialists around the world were consulted either in person or by correspondence during its preparation.