Lecture : Contents 1. What is auxiliary LT (ALT)? 2. When does ALT need? 3. What is issues of ALT for acute liver failure (ALF)? 4. Who can be a good candidate for ALT? 5. How to carve out a niche of technical challenges 6. How to manage Post-ALT patients 7. A SNUH case: A video clip 8. Reappraisal of ALT for ALF for Expanding Organ Utility Summary An APOLT (auxiliary partial orthtopic liver transplantation for ALF has a benefit of immunosuppressant discontinuation in 60-100% without compromising patients’ survival outcome. This can also provide to expand the donor pool in some aspect. However, it’s technically challenging as well as graft function and native liver regeneration is usually unpredictable. Thus, selection of good candidates (young, biopsy guided, hemodyenamically stable) and delicate surgical modification are important to lead a successful APOLT for ALF. In addition, this should be supported by careful postoperative monitoring and slow/steady immunosuppressant withdrawal after confirmation of native liver function restoration.