In this chapter an overview is presented on the state of knowledge concerning the toxicokinetics of sulfur mustard. The procedures to analyze intact sulfur mustard in the blood and tissues of laboratory animals at toxicologically relevant levels are discussed. In view of the fact that the reviewed toxicokinetic studies were performed one to three decades ago, this chapter also describes how the analysis would be performed with the techniques that are available today. The various animal models used, e.g., rats, hairless Guinea pigs, pigs and marmosets, are discussed with respect to their advantages and drawbacks. The toxicokinetics of intact sulfur mustard in the blood and tissues are presented for various routes of exposure, including the highly relevant respiratory and percutaneous routes, using intravenous administration as the reference route. In addition, the time course of the predominant adduct to DNA in the blood and various tissues is described. Furthermore, data on sulfur mustard metabolites and adducts measured in humans accidently exposed to the agent are presented and discussed in the light of the observations in laboratory animals. Several knowledge gaps are identified, and suggestions are made about how to fill these. Â© 2016 The Royal Society of Chemistry.