A series of papers in Philosophy, Ethics and Humanities in Medicine (PEHM) have recently disputed whether non-heart beating organ donors are alive and whether non-heart beating organ donation (NHBD) contravenes the dead donor rule. Several authors who argue that NHBD involves harvesting organs from live patients appeal to "strong irreversibility" (death beyond the reach of resuscitative efforts to restore life) as a necessary criterion that patients must meet before physicians can declare them to be dead. Sam Shemie, who defends our current practice of NHBD, holds that in fact physicians consider patients to be dead or not according to physician intention to resuscitate or not. We suggest that criteria for a concept are not necessarily truth conditions for assertions involving the concept. Hence, non-heart beating donors may be declared dead without meeting the criterion of strong irreversibility even though strong irreversibility is implied by the concept of death. Our perception that a concept applies in a given case is determined not by the concept itself but by our necessary skill and judgment when using it. In the case of deciding that a patient is dead, such judgment is learned by physicians as they learn the practice of medicine and may vary according to circumstances. Current practice of NHBD can therefore be defended without abandoning death as an empirical concept, as Shemie appears to do. We conclude that the dead donor rule continues to be viable and ought to be retained so as to guarantee what the public most cares about as regards organ donation: that physicians can be trusted to make determinations of eligibility for organ donation in the interests of patients and not for other purposes such as increasing the availability of organs. © 2008 Huddle et al; licensee BioMed Central Ltd.