Biometric identification is not just a more technologically advanced form of identification: it implies a radically new conception of what constitutes a person’s identity. Based on the case study of the first biometric voter registration in Chad, this chapter shows that such large-scale registration schemes are not a neutral operation. They reinvent the population and render lives and bodies more ‘legible’, even more so in a state that until recently had little interest in the population and no detailed, individualized information about it. I argue that lives and bodies have undergone two distinct, yet related, stabilization or fixing processes: on the one hand, the bureaucratic rationalization of names and biographies, and on the other, the capture of body features to meet standardized global norms. Ultimately, it shows that the collection of biometric and biographic data does not automatically strengthen the state’s surveillance abilities and is not sufficient to radically modify the mode of government.