Lung transplantation has become an established rescue therapy for patients with end-stage disease. The major problem, however, is the shortage of organ donors. Living related donation has been successful in kidney and liver transplantation and, recently, in lobar lung transplantation as well. The main ethical dilemma is whether we should risk a parent family member in order to save a child or relative. This dilemma can be taken to the extreme in a case in which pneumonectomy from a live donor can save a patient who is in need of single lung transplantation, a procedure that has not yet been performed, although technically feasible. We discuss the ethical aspects of such a procedure from the perspectives of the donor, the recipient, and the medical team.