Does forming accurate impressions benefit emerging relationships? In 2 longitudinal studies (Study 1: 235 participants, 534 dyads, 2 time points; Study 2: 122 participants, 3,023 dyads, 7 time points), we examined whether more accurate personality impressions among new acquaintances fostered greater liking over time for both the perceiver and target (accuracy fosters liking hypothesis). Further, we examined whether greater perceiver and target liking also fostered accuracy over time (liking fosters accuracy hypothesis). Overall, we found partial support for the accuracy fosters liking hypothesis: Greater accuracy (distinctive accuracy about a target's unique self-reported personality traits) fostered greater perceiver but not target liking over time. However, we did not find support for the liking fosters accuracy hypothesis, as neither perceiver nor target liking fostered greater accuracy over time. Going further, for the accuracy hypothesis, there was preliminary evidence that the strength of the associations depended on partner liking, such that accuracy was more beneficial for perceiver liking when target liking was high, and vice versa. These associations emerged above and beyond the strong, expected associations between liking and forming normative, positive personality impressions. In sum, these studies demonstrate that accurate personality impressions may indeed be adaptive, benefitting early relationship development, at least from the perspective of the perceiver. (PsycINFO Database Record (c) 2019 APA, all rights reserved).