Is there a relationship between cultural and biological diversity? Are these diversities under threat in our ever more globalizing world, and do we need to safeguard them? Can sacred natural sites and associative cultural landscapes play a role in conserving both cultural and biological diversity? These and related questions on the interrelationship between the natural and cultural diversity of our planet were addressed at the international symposium on "Conserving Cultural and Biological Diversity: The Role of Sacred Natural Sites" which took place at the United Nations University (UNU) in Tokyo from 30 May to 2 June 2005.