This chapter focuses on the concept of “governing through contagion.” Flexing power over life, governing through contagion regulates subjects of a population to ensure their bodies are free from contagion, do not spread contagion to fellow subjects, and stay economically productive—or at least, avoid incurring economic costs of medicine and containment. In many territories, the legal strategies of control in response to the Covid-19 pandemic, such as quarantine orders and movement restrictions, grew out of earlier episodes of contagion that significantly shaped governing through contagion. The chapter then introduces three themes of governing through contagion: centralization and technology of law; normalization and technologies of moralization; and inter/dysconnectedness and the rearticulation of difference. The analysis draws on the historical ethnography of one British post-colony, Singapore, situated in three contexts: the colonial era (particularly 1868–1915), which was troubled by numerous epidemics such as plague, cholera, and smallpox; the 2003 Severe Acute Respiratory Syndrome (SARS) outbreak; and the Covid-19 pandemic.