At its general conference in Paris on 16 October, the United Nations educational, scientific and cultural organisation (UNESCO) adopted the international declaration on human genetic data. In laying down the ethical principles that should govern the collection, processing, storage and use of human genetic data, the declaration's stated aim is to ensure the respect of human dignity and the protection of human rights. The document also gives due consideration to freedom of thought and expression, including the freedom of research, says UNESCO. Earlier the director general of UNESCO, Koïchiro Matsuura, had told the conference: 'I could never overstate the urgency with which we must adopt such a declaration, because every day brings more new experiments and initiatives, some of which could have irreversible consequences.' Human genetic data are derived from biological samples such as blood, tissue, and saliva, and are increasingly being stored in genetic data banks around the world. Not only can they be used to identify in advance which diseases threaten us, but they also represent a promising source of new cures, and are increasingly being used to establish paternity, or guilt in criminal investigations. Given the obvious potential for such information to be misused, UNESCO, through its international bioethics committee, began an examination of the issues related to human genetic data, including a process of extensive international consultation. The resulting declaration asserts that the collection of human genetic material should be based on 'prior, free, informed and express consent, without inducement by financial or other personal gain.' The right to decide weather or not to be informed of research results is also considered. When using human genetic data in scientific experiments, the declaration considers that data collected for one purpose should not be used for a different purpose that is incompatible with the original consent. More generally, the declaration also calls for the promotion and establishment of independent multidisciplinary ethics committees at national, regional, local or institutional levels, and for the conclusion of bilateral and multilateral agreements that will enable developing countries to participate in generating and sharing the scientific knowledge resulting from the investigation of human genetic data.