Haematopoietic or blood-forming stem cells are immature cells that can mature into blood cells. These stem cells are found in the bone marrow, bloodstream, or umbilical cord blood. Bone marrow transplantation (BMT) and peripheral blood stem cell transplantation (PBSCT) are procedures that help restore stem cells that have been destroyed by high doses of chemotherapy and/or radiation therapy.

There are three types of transplants:

Allogeneic transplant - patients receive stem cells from their brother, sister or parent; or from an unrelated donor
Syngeneic transplant- patients receive stem cells from their identical twin
Autologous transplant - patients receive their own stem cells