Although alcohol use has been established as a risk factor for injuries associated with motor vehicle crashes, the role of alcohol for other unintentional and intentional injuries is less defined. A review of 102,401 deaths investigated by North Carolina medical examiners in the period 1973-1983 characterized the temporal patterns of ethyl alcohol in unintentional injury fatalities, suicides, homicides, and persons who died of natural or unknown causes. Victims of homicides (85.9%) and suicides (77.7%) were tested for alcohol more frequently than were fatalities resulting from unintentional injury (67.5%) or natural causes (61.6%). Alcohol was present in 62.8% of homicide victims, 48.6% of unintentional injury fatalities, 35.3% of suicides, and 14.4% of deaths from natural causes. The percentage of alcohol-associated deaths for each manner of death showed little yearly or seasonal variation. Alcohol was most frequently detected in persons fatally injured on the weekend and from 6 PM to 6 AM. This study highlights the magnitude of alcohol's role in intentional and unintentional injuries, especially for persons injured at night and on weekends.