I offer a reconstruction of contemporary medical procedures of sex assignment for infants with intersex conditions. In the perspective adopted, sex assignment to intersexed newborns can be understood as a procedure that imposes determinate sex predicates. The account describes two stages of sex assignment. At the first stage of the process, the sex predicates ‘female’, ‘male’, or ‘intersexed’ are taken to denote genital morphology. Initial genital assessment of newborns imposes clear boundaries upon the extensions of these predicates through diagnostic schemes (...) of precisification. At the second stage, the sex predicates ‘female’ and ‘male’ denote sex of rearing, a therapeutic and pedagogical project aimed at producing stable and psycho-socially well-adjusted gender identity. The multi-dimensional indeterminacy of prognosticating sex of rearing at the second stage is mitigated through the prioritization of some subsets of the medical data. (shrink)