People who report frequently using cognitive reappraisal to decrease the impact of potentially upsetting situations report better affective functioning than people who report using cognitive reappraisal less frequently. However, most work linking everyday reappraisal use to affective outcomes has been correlational, making causal inference difficult. In this study, we examined whether 2 weeks of daily practice of reappraising negatively valenced personally relevant events would improve affective functioning compared with a wait-list control. Data were collected between 2021 and 2022 from a sample mainly comprised of females (82%) and who identified as Asian (35%) or White/Caucasian (40%). Our planned analyses indicated that reappraisal decreased depressive symptoms and perceived stress as well as increased life satisfaction both immediately and 4 weeks postintervention. Reductions in depressive symptoms and perceived stress were mediated by increases in reappraisal self-efficacy. These findings support the causal efficacy of brief reappraisal training. (PsycInfo Database Record (c) 2024 APA, all rights reserved) (Source: journal abstract)