 The widespread acceptance in the U.S. of the whole-brain standard and the broader international acceptance of some sort of “brain death” criteria—whether whole-brain or brainstem—are remarkable considering the subtlety of issues surrounding the definition and determination of death. Yet this near-consensus has been broader than it is deep. Increasingly, both in academic and clinical circles, doubts about “brain death” are being voiced. Following are several major challenges to the whole-brain standard—and, implicitly, to the brainstem standard. (Several additional challenges are implicit in arguments supporting the higher-brain approach.)