Patients who donate their organs are called organ donors; patients who receive the donor organs are called organ recipients. With the exception of those who donate a portion of a liver or a single kidney, most organ donors are brain-dead. Transplant patients often have to wait months or even years for a transplant to come their way by putting their name on a list. In Grey's Anatomy, the fictionalized version of real-life organization U.N.O.S. coordinates transplant patients and donors.