Organ donation and transplantation

Common organs and transplantable tissues

Modern transplantation includes a defined set of organs and a wider range of tissues. Major solid organs transplanted include:

• Heart
• Kidney
• Liver
• Lung
• Pancreas
• Intestine

Transplantable tissues include corneas, skin and musculoskeletal components, and vascular conduits. Examples are:

• Cornea for vision restoration
• Skin grafts for burns and reconstruction
• Bone, muscle, and tendon for orthopedic repair
• Veins and other vessels used in reconstructive surgery
• Specialized tissues such as the thymus in pediatric cases

Types of donation and clinical considerations

Living donation often involves a person giving a kidney or a portion of their liver to a relative, friend or an anonymous recipient. Deceased donation occurs after death is declared under legal and medical criteria; organs are recovered and preserved for transplant. Matching for blood type, tissue markers and organ size is required, and recipients commonly need lifelong immunosuppressive medication to prevent rejection. The transplant operation itself is complex: teams perform careful planning, timing and surgery to minimize ischemic injury and improve outcomes.

History, demand and allocation

The practice of human organ transplantation developed in the mid-20th century, with early successes in renal grafts and improvements in surgical technique, anaesthesia and immune suppression that made solid-organ transplants routine. Demand for organs greatly exceeds supply in most countries, leading to waiting lists, prioritization policies and allocation systems designed to balance fairness, urgency and likely benefit. Kidneys are among the most frequently transplanted organs worldwide, followed by livers and hearts; among tissues, corneas, bone and skin are commonly used.

Legal, ethical and social issues

Consent models vary: some nations operate opt-in systems requiring explicit donor authorization, while others use opt-out or presumed-consent frameworks. Living donation raises ethical questions about undue inducement, risk to donors and long-term follow-up. Commercial trade in organs is widely prohibited and condemned by international bodies because it can exploit vulnerable people; a notable exception often cited in debates is Iran, which has regulated payment for a kidney donor under a specific national program. Many countries and organizations emphasize voluntary, altruistic donation to protect donors and recipients.

Research, innovation and future directions

Transplant medicine continues to evolve. Improvements in immunosuppression, infection control and organ preservation have increased graft survival. Research in regenerative medicine and tissue engineering aims to grow organs or create replacement tissues from stem cells or scaffolds, which could reduce dependence on donor supply. Meanwhile, public education, donor registries and coordinated logistics remain central to increasing safe donation and saving lives. For more clinical and policy resources see related entries on organ types and tissue banking (tissues), transplantation operation guides (transplant) and organ-specific information such as kidney and liver.