We investigated the development of the other-race effect "ORE" in a longitudinal sample of 3-, 6-, and 9-month-old Caucasian infants. Previous research using cross-sectional samples has shown an unstable ORE at 3 months, an increase at 6 months and full development at 9 months. In Experiment 1, we tested whether 9-month-olds showed the ORE with Caucasian and African faces. As expected, the 9-month-olds discriminated faces within their own ethnicity (Caucasian) but not within the unfamiliar ethnicity (African). In months. In Experiment 2, we longitudinally tested infants at 3, 6, and 9 months by presenting either the Caucasian or the African faces used in Experiment 1. In contrast to previous cross-sectional studies and Experiment 1, we found that infants discriminated between all stimuli. Hence, we did not find the ORE in this longitudinal study even at 9 months. We assume that the infants in our longitudinal study showed no ORE because of previous repetitive exposure to African faces at 3 and 6 months. We argue that only a few presentations of faces from other ethnic categories sufficiently slow the development of the ORE. (Contains 2 tables and 2 figures.)