Advances in life-saving technologies in the past few decades have challenged our traditional understandings of death. People can be maintained on life-support even after permanently losing the ability to breathe spontaneously and remaining unconscious and unable to interact meaningfully with others. In part because this group of people could help fulfill the growing need for organ donation, there has been a great deal of pressure on the way we determine death. The determination of death has been modified from the old way of understanding death as occurring when a person stops breathing, her heart stops beating, and she is cold to the touch. Today, physicians determine death by relying on a diagnosis of total brain failure or by waiting a short while after circulation stops. Evidence has emerged that the conceptual bases for these approaches to determining death are fundamentally flawed and depart substantially from our biological and common-sense understandings of death. We argue that the current approach to determining death consists of two different types of unacknowledged legal fictions. These legal fictions were developed for practices that are largely ethically legitimate but need to be reconciled with the law. However, the considerable debate over the determination of death in the medical and scientific literature has not informed the public of the fact that our current determinations of death do not adequately establish that a person has died. It seems unlikely that this information can remain hidden for long. Given the instability of the status quo and the difficulty of making the substantial legal changes required by complete transparency, we argue for a second-best policy solution of acknowledging the legal fictions involved in determining death. This move in the direction of greater transparency may someday result in allowing us to face squarely these issues and effect the legal changes necessary to permit ethically appropriate vital organ transplantation. Finally, this paper also provides the beginnings of a taxonomy of legal fictions, concluding that a more systematic theoretical treatment of legal fictions is warranted to understand their advantages and disadvantages across a variety of legal domains.