Erik M. P. Widmark (1889-1945) was among the first researchers to study in a systematic way the absorption, distribution, and elimination of ethanol in the body; in addition, he formulated his results in mathematical terms. Widmark's research during the first decades of this century paved the way for innovative traffic safety legislation that stipulated punishable limits of alcohol in the blood of a person driving a car. The 50th anniversary of Widmark's death was commemorated in 1995. His contributions have gained enormous respect and are still widely cited in forensic science, especially in connection with the crime of driving under the influence of alcohol. The Widmark equations and the factors β andrare now part of the vocabulary of all those trained in forensic alcohol analysis and toxicology.