Graft failure occurs when a transplanted tissue or organ, known as a graft, does not function properly or is rejected by the recipient's body. This can happen due to various reasons, including inadequate blood supply, infection, or the body's immune response attacking the graft as a foreign object. There are two main types of graft failure: acute and chronic. Acute graft failure happens suddenly, often within days or weeks after the transplant, while chronic graft failure develops gradually over months or years. Successful management of graft failure often requires medical intervention, including medications to suppress the immune system.