Confessions are commonplace. Even when embarrassing or otherwise damaging, we seem intrinsically motivated to open up to others and confess mistakes we have made. Although there may be many reasons one might choose to disclose one's "sins," very little is known about what confession actually does, particularly concerning its effect on future behavior. This work examines confession in the context of one's personal self-control failures in consumption, asking the central question: does confession lead to repentance (i.e., enhanced subsequent self-control) or relapse (reduced subsequent self-control)? We predict and demonstrate that the effect of confession on ensuing behavior depends largely on the amount of guilt a confessor feels regarding their behavior prior to confession. Across five studies, we find that confessing (versus not confessing) high-guilt transgressions boosts subsequent self-control, whereas confessing relatively low-guilt indiscretions promotes further relapse. Further, initial evidence suggests that changes in self-discrepancy following a confession drive subsequent changes in self-control behaviors. A single paper meta-analysis demonstrates the robustness of our key effects and provides further support for the role of self-discrepancy in the underlying process. (PsycINFO Database Record (c) 2019 APA, all rights reserved).