In an effort to document better the role of alcohol in motor vehicle traffic accidents in Canada, two studies were conducted. One examined the blood alcohol levels of drivers reporting to emergency wards in New Brunswick; the second study examined alcohol levels among fatally injured drivers. This paper describes these studies, and provides an examination of the overall relationship between driver blood alcohol level and injury severity. It was found that injury severity increased as a function of BAC; reasons for this relationship are discussed. It is argued that alcohol consumption exerts its effects not only upon increasing the likelihood of collision occurrence, but also upon factors associated with collision outcome severity.