Organ transplantation is a medical procedure in which an organ is removed from one body and placed in the body of a recipient to replace a damaged or missing organ. The donor and recipient may be at the same location or organs may be transported from a donor site to another location. Organs or tissues that are transplanted within the same person's body are called autografts. Transplants that are recently performed between two subjects of the same species are called allografts. Allografts can either be from a living or cadaveric source.