Self-enhancing and self-improving motivations were investigated in North American (Canadian and American) and Japanese university students. Conceptually replicating much of the self-enhancement and self-efficacy literatures, North Americans who received failure feedback persisted less on a follow-up task than those who received success feedback. In contrast, Japanese who received failure feedback persisted more on a follow-up task than those who received success feedback. This tendency to respond to failure with increased efforts is evidence for a self-improving orientation among Japanese: an awareness of shortcomings highlights where corrective efforts are needed. Japanese who had failed also enhanced the importance and the diagnosticity of the task compared to those who had succeeded, whereas North Americans exhibited the opposite pattern. Study 2 revealed that these self-improving motivations are specific to the tasks on which one receives feedback. Study 3 "unpackaged" the cultures by demonstrating that these cultural differences are ue, at least in part, to divergent lay theories regarding the utility of effort. Study 4 ddressed a problem with contrasting cultures on subjective Likert scales and replicated these cultural differences with a different measure.