Death dates comprise a critical piece of mortality data for studying disease burden. This paper reviews various sources of death dates available for disease burden studies and evaluates them in terms of their completeness and accuracy. Civil registration systems are the most frequently used sources of dates and causes of death for Global Burden of Disease studies and other studies of population health. A review of the mortality data submitted to the World Health Organization suggests that tremendous variations in the completeness and coverage exist from country to country and large improvements in the quality of civil registration systems are still to be achieved. For studies of disease burden that require person-level data, not only the civil registration systems but some alternative sources can be utilized. These alternative sources may not have the completeness and accuracy of the data from the civil registration systems, but when they are combined judiciously they can be a valuable source of death dates that can match the civil registration system in completeness and accuracy.