This case study introduces students to John Snow, considered to be one of the founders of both epidemiology and anesthesiology, and a remarkable figure in the history of science. Although historical case studies are often less popular with students than contemporary issues (Herreid 1998), a number of aspects of this case make it attractive to students. First, students find the “detective stories” about important medical discoveries to be inherently appealing. Second, the questions and methods that Snow used to demonstrate the causes of cholera outbreaks are the basis for those used in contemporary epidemiological investigations. Third, although the case study is built around a historical event, there are contemporary cholera outbreaks with some parallels to those studied by Snow (e.g., WHO 2008).