In particular, self-derogation theory predicts that low self-esteem motivates youths to try out delinquent activities that are aimed at restoring self-esteem. While the correlation between self-esteem and delinquency has been widely studied, the proposition that delinquent behavior can have self-enhancing effects remains uncertain and undocumented. This study examines some conditions under which engaging in delinquent behaviors may boost self-esteem. Applying multivariate procedures (dummy variable regression) to the Youth-in-Transition data panel, the article tests and estimates the combined effects of initial self-derogation and participation in delinquency on subsequent self-attitudes. The results show a curvilinear (second-order) interaction where self-enhancement from delinquent behavior occurs mainly among youths whose self-esteem is extremely low and whose self-esteem needs are unusually high. These effects appear to be quite persistent, enduring undiminished over a one-and-one-half to three-and-one-half-year lag. An additional and unpredicted finding is that delinquency may also show occasional enhancing effects among persons with very high self-esteem. (Author abstract) 4 tables, 5 figures, 18 references.