Pre-transplantation preparation phase: done mainly in outpatient clinics. Pre-treatment stage: The recipient receives high doses of chemotherapy or radiotherapy, during which the white blood cells also gradually drop to lower levels. Transplantation stage: Blood stem cells from the donor are transfused back to the recipient through a vein, and the recipient lives in a laminar flow clean room. Early post-transplantation period: The recipient lives in a laminar flow clean room while the hematopoietic stem cells are being implanted in the recipient’s body and the blood cells are recovering to a safer level. Middle post-transplantation period: After the donor’s blood stem cells have been implanted in the recipient, the recipient is under observation in a general ward. During this period, post-transplant complications are mainly observed or treated, and the recipient can be discharged if he/she is in good general condition and has no serious complications. Late post-transplantation period: Patients are discharged from the hospital for regular outpatient follow up, depending on the type of transplantation until about 3 months – 6 months after transplantation, if the condition is stable, they can return to the local area, then return to the hospital every 3-6 months for review until 2 years after transplantation, and then return to the hospital once a year for review until 5 years after transplantation. In some cases, the doctor in charge may set a special review interval according to the condition.