This chapter takes a transnational approach to the study of the administration of quarantine, considering the how boards of health had to operate along local, national, and international registers. Through a social and institutional study of quarantine administration, it becomes clear how boards in different countries negotiated problems in symmetry. The chapter explores the administrative logic underlying disinfection practices and the daily scope of board of health activities. Lazarettos comprised a rigid hierarchy of employees, from the “Captain/Prior” in charge of the building through doctors to the “guardians” who attended each traveling party and who cycled in and out of quarantine themselves. At the top of the hierarchy, boards of health wielded immense power as they acted as local administrators with an international remit. I investigate how the lazaretto could simultaneously serve as an economic engine for cities such as Marseille, a civic institution, and a space that fell within the interstices of administration, whose jurisdictional status remained murky.