Brain death is defined as the complete and irreversible absence of all brain function including profound coma, apnea, and absence of all brain stem reflexes. It is diagnosed by means of rigorous testing at the bedside, in addition to confirmatory tests such as electroencephalogram which vary from country to country. As technological complexity and advancements in critical care continued to explode during the past several decades, brain death as a new concept of death emerged and evolved as a necessary measure for determining death. Before the development of these neurological criteria, death was classically described as the cessation of circulation and respiration. The major reason for medical, community, and legal acceptance of brain death is the need for organ donation from “beating heart” donors. A declaration of brain death is only used for this purpose, and not for withdrawal of life support measure which are useless once brain death is declared.The present study aimed to assess brain death as regarding the common causes, patients’ age, clinical criteria and different durations of progression to coma, brain death and cardiovascular death.