Adult-to-adult living donor liver transplantation (ALDLT) is a reality; shortly after its introduction into clinical practice, it is being performed in approximately 50 centers throughout the United States and Europe. The quick development of ALDLT and some deaths among donors repropose old ethical dilemmas and confront the transplant community with new urgent problems. To minimize risks for recipients and, especially, donors, two key questions are addressed: (1) who can or should perform the procedure, and (2) what patient should undergo the procedure. The high risks taken by live donors undergoing a hemihepatectomy seem to be justified by the steadily increasing mortality of adult recipients waiting for transplantation. A comprehensive consent procedure is at the base of responsible decision making for both donors and recipients. In adherence to basic medical criteria, the autonomy of decision of donors and recipients may allow the extension of indications to patients not suitable to undergo transplantation with cadaveric grafts. The broadening of indications is appropriate only in centers with adequate experience and proven expertise in ALDLT. The medical community faces the duty of regulating ALDLT before external influences force undesired policy changes, particularly if not based on medical grounds. Individual centers and patients are ultimately responsible for the correct use of LDLT.