William Bryan Jennett, one of the leading figures in neurosurgery of the twentieth century, has died on 26 January 2008, at the age of 81. He made fundamental contributions to the field of traumatic brain injury (TBI) that still shape diagnosis, management and prognosis worldwide, in the second part of the last century. This paper is meant to gratefully acknowledge his contributions and to reflect on the implications that his work has for neurointensive care today. Starting from his early steps, we tried to highlight his fundamental work on diagnosis of severity in TBI, on rescue, treatment and prognosis of severe TBI. Moreover, his contribution in the definition of vegetative state, minimally conscious state and brain death has been emphasized. The contribution of Professor Bryan Jennett was in fact seminal in many aspects: the application of a common language in brain damage evaluation, where GCS and GOS are now universally employed; a critical approach to TBI diagnosis and treatment, in the search of proven better therapies; a quantitative approach to TBI prognosis, based on large clinical series and appropriate statistics; a strong commitment to the ethical implication of survival after severe injury, including the vegetative status; social responsibility in the diagnosis of brain death and in organ donors procurement. For these reasons, he can be considered one of the leading figures in neurosurgery and neurology of the twentieth century. This paper is meant to gratefully acknowledge his contributions and to reflect on the implications that his work has for neuro-intensive care today.