This essay develops a remark Foucault made in passing at the end of the first volume of The History of Sexuality (1976), linking the emergence of bio-power and the nineteenth-century sociological fascination with suicide. Foucault traced the origins of bio-power in his CollΓ¨ge de France courses of 1977β1978 and 1978β1979, but never returned to the relationship between the sociological appropriation of suicide and this uniquely modern form of power. Using the recently published lectures from these courses, this essay interprets two nineteenth-century sociological treatises on suicide as historical examples of the development of βgovernmentality.β The first text is a commentary on suicide from the MΓ©moires (1838) of Parisian police administrator Jacques Peuchet, which the young Marx translated and published in 1846. This proto-sociological text is interpreted as an early manifestation of governmentality, while the second text, Durkheimβs Le Suicide (1897), is presented as a classic of sociology and governmental rationality. Aside from the light it sheds on the historical relationship between sociology, governmentality, and suicide, this essay also illuminates some often-overlooked implications of the current βright to dieβ movement.