The ABMDR is part of a worldwide network of unrelated donor registries. It was established in 1991 as a register of people who are willing to donate their bone marrow or haemopoietic stem cells (HSC) if they are found to be a suitable match for a patient needing a bone marrow transplant. The ABMDR provides access to a global database of volunteer donors and cord blood units for patients who require a bone marrow or haemopoietic stem cells transplantation but have not found a suitable matched sibling or relative.