Self-discrepancy theory (SDT) postulates that self-regulatory systems corresponding to the ideal and ought self-domains emerge from the influences of temperament (e.g., sensitivity to stimuli for positive vs. negative outcomes) and socialization (e.g., parenting behaviors and interpersonal outcome contingencies). This article reports 2 studies testing the developmental postulates of SDT concurrently and retrospectively. Study 1 showed that self-regulation with reference to the ideal vs. the ought domain was differentially associated with recollections of parenting styles of warmth and rejection, respectively. In Study 2, these findings were replicated, and self-regulation with reference to the ideal vs. ought domain was discriminantly associated with questionnaire measures of positive vs. negative temperament. Findings support the developmental postulates of SDT, despite the limitations of retrospective studies.