Registered Members    Remember credentials Xenome is an integrated project in the European Sixth Framework Programme (Life Sciences, Genomics and Biotechnology for Health). As a result of improved medical and technological interventions in the field of transplantation, an increasing number of people are now listed for transplants. It is estimated that approximately 45,000 people are currently on waiting lists for any kind of organ transplant in the different EU member states. Efforts to increase organ donation, to improve the usefulness of sub-optimal organs and to utilise organs from living-related donors represent important corrective steps. However, current figures indicate that these approaches are unlikely ever to fully meet demand. In an effort to meet the demand for organs for transplantation, many different avenues are being explored. These include the development of artificial organs, tissue engineering and xenotransplantation. According to the most recent guidelines of the European Union, a xenotransplant is defined as any procedure that involves: •  the transplantation, implantation or infusion to a human recipient of organs, tissues or viable cells of animal origin (type A xenotransplant) or •  the ex vivo contact of human body fluids, cells, tissues or organs with live cells, tissues or organs of animal origin (type B xenotransplant). Recent scientific developments indicate that transplantation of organs, tissues or cells between species may at some stage become a realistic option, ultimately resulting in an increased supply of organs to meet medical demand. However, in order to allow the clinical application of xenotransplantation, several immunological, biosafety, physiological, regulatory, social and ethical issues still need to be adequately addressed. In this light, in order to generate the necessary data to allow xenotransplantation to progress towards its initial clinical phase, the European Union has provided funding for XENOME, a European Commission-funded multidisciplinary effort through which the EU will be present in this scientific field for the next 5 years.