Laboratory experiments and surveys show that self-objectification increases body shame, disrupts attention, and negatively predicts well-being. Using experience sampling methodology, the authors investigated self-objectification in the daily lives of 49 female college students. Building on the predictions of objectification theory, they examined associations between internalizing an observer's perspective on the self and psychological well-being, and examined the moderating roles of trait self-esteem and appearance-contingent self-worth. Within-person increases in self-objectification predicted decreased well-being, but this association was moderated by trait self-esteem and trait appearance-contingent self-worth; high self-esteem, highly appearance-contingent participants reported increased well-being when they self-objectified. Furthermore, perceived unattractiveness partially mediated the main effect and the three-way interaction: high self-esteem, highly contingent participants experienced smaller drops in well-being when they self-objectified, in part because they felt less unattractive. These results suggest that in daily life, some women receive a boost from self-objectification, although most women experience decreases in well-being when self-objectifying.