Principle purpose of this lecture is to present on Transplantation Immunology. Here briefly focus on Organ and Tissue Transplantation; Immunosuppressive Agents and Immunosuppressive Therapy. Transplantation immunology – sequence of events that occurs after an allograft or xenograft is removed from donor and then transplanted into a recipient. A major limitation to the success of transplantation is the immune response of the recipient to the donor tissue. Here also briefly present on types of Transplant: Autograft, Isograft, Allograft and Xenograft.