The introduction outlines the relations between the historical and contemporary aspects of habit's political histories—between “habit then” and “habit now.” It also discusses how the metaphor of “habit's pathways” offers a point of entry into these histories in view of how habit has been constituted as a form of behavior that needs either to be kept on the same track or to be broken with to pave the way for the adoption of new forms of conduct. The upswing of interest in habit in the politics of the present is related to other periods in Western thought when habit has been a hot political topic: the Reformation, the early development of liberal political thought, and engagements with both of these earlier moments in the nineteenth-century empirical sciences of man. The principles informing the book's critical engagements with the “wayward tradition” of habit theory associated with post-Deleuzian thought are outlined.