The proposed project pertains to the ways in which various European nations (i.e., Britain, France, German, and Sweden) intervened against contagious diseases during the period 1830-1930. Most broadly, the theme explored is the relative weight attached to the rights of the individual against coercion in light of the claim of the community to defend itself against a common threat. The Principal Investigator will seek to analyze the significant variation that existed among nations in terms of how interventionist they chose to be and will attempt to account for the reasons behind the choices. More specifically, he will study a series of diseases and the measures taken to fight them: (1) the cholera epidemics starting in the 1830's and the laws of quarantine and isolation that were used to combat them until Koch's discovery of the disease's cause; (2) smallpox and the laws passed (and, in some cases, repealed) on compulsory vaccination; (3) venereal disease and the laws on the regulation of prostitution; and (4) the series of International Sanitary Conferences that were held throughout the 19th century in an attempt to agree on measures to keep cholera and other infectious diseases out of Europe. The proposed project is part of a larger ongoing study of the evolution of state intervention; in it, medical history will be used the hope of illuminating broader trends of state development.